Despite being a once popular meditation method, Transcendental Meditation teachers are probably the least informed and experienced "teachers" of meditation I know of. After all, they're really not trained in the mechanics of meditation, but marketing. A recent article by TM proponent and long-time TM teacher Tom Ball is a perfect example. Let's look at how much is understood about meditation praxis and how confused some people are as to what the differing types of meditation are, and why.
Transcendental Meditation, Mindfulness And Enlightenment
As is typical in Transcendental Meditation advocates, they will often posit false or ignorant statements, and then use they false assertions to try to forward their beliefs. What they are actually doing is creating a "straw man", an argument based on a false image from their own imagination or ignorance. Already in this first paragraph they've mislead the reader.
Ball states Mindfulness can easily be learned from a book or a therapist, etc. And of course, what he doesn't tell you that TM is often taught through books and tapes, or by instructions posted on the internet! But what Ball ignores is how Mindfulness is most often taught: it's most often taught in 7-10 day courses, although some people teach it over a long weekend, the 1 week or longer track is more traditional and in many ways more typical. One often receives meditational instructions from a seasoned meditator with years of inner experience in different forms of meditation. So instead of having to rely on "canned" and simply memorized "checking instructions" (a flowchart of instructions TM teachers are required to memorize), experienced meditators rely on their own extensive inner experience, tailored individually to the student.
Although both forms of meditation produce relaxation and practitioners may report some similar benefits—such as inner calm and centeredness, pain management or greater awareness and focus during the day—these techniques differ considerably, both in practice and range of effects as measured by scientific research.
Ah, here we go. Another set up. TM advocates will often cite "scientific research" on TM--but they'll fail to mention that TM research has a long, long history (several decades) of poor research. In fact TM research is so bad, it was even dismissed as "poor" in recent studies sponsored by the US government! The idea of good meditation research, is to improve and refine. Not these TM researchers! They're still putting out pilot studies and junk science after 40 years!
We'll look more into the specifics of the poor record of TM research a little later.
What is mindfulness meditation?
Mindfulness meditation (or guided mindfulness) generally involves watching one's thoughts, the breath or bodily sensations while sitting quietly. Typically the student does not judge or hold on to thoughts or perceptions, but merely observes them. Mindfulness is often described as the process of being attentive to one’s experiences. This practice of being mindful may also extend into daily activity, as one adheres to dispassionate observation of thoughts and actions in order to be more fully present in the moment and not overshadowed by passing concerns.  The practice of mindfulness takes place in what psychologists and neuroscientists generally call the waking state of consciousness, different from the sleep or the dream states.
Not a very good description, I have to say.
First it's important to explain what are the two basic forms of meditation that are taught in many Buddhist settings. These two meditation forms are 1) Mindfulness or Vipassana and 2) Shamatha or Calm Abiding meditation. Transcendental Meditation is a rudimentary practice of this latter type. But strangely here, we see no recognition or understanding of this basic fact.
Beginning meditators are welcome to begin with either a Mindfulness style of meditation or a Calm Abiding style, each one has it's own unique benefits. Advanced meditators learn they can actually unify both forms into something greater than the sum of the two: nondual meditation.
What is the Transcendental Meditation technique?
During the practice of the Transcendental Meditation technique, the mind spontaneously transcends, going beyond the mental activity of waking state to a unique state of restful alertness, called Transcendental Consciousness—a proposed fourth state of consciousness unlike waking, dreaming or sleep.
Independent studies of TM meditators show that this claim is actually false. Most TM meditators are actually in descending stages of sleep. Despite many wild and fanciful claims, there is no evidence that TM produces any "state of consciousness" outside of waking, dreaming or sleeping states. In fact, when the EEG or electroencephalographs of actual yogis are compared to those of advanced TM meditators, they are quite different. The reason they are different is that while TM induces the same EEG and "relaxation response" found in many different forms of meditation, they do not produce the types of EEG changes seen in advanced meditators. This point is well known by leading scientists, but dutifully ignored by TM researchers (who are often TM meditators themselves!).
This easy meditation involves using a mantra, or sound without meaning, that has a harmonizing effect on the mind and body, producing deep relaxation and quieter mental activity. Because deeper levels of the mind are more concentrated with energy, creativity and intelligence, one's awareness becomes infused with these qualities as the meditator experiences the inner depths of consciousness.
While I know from having spoken directly to many TM teachers that they were taught to tell students that their mantras were meaningless, this is not in fact the case. All of the TM mantras are listed in lengthy ancient books, encyclopedias of mantra, called koshas in Sanskrit. The koshas describe in exquisite detail the meaning and mechanics of all of the TM mantras, and many more. All of the TM mantras are mantras of various Hindu Gods and Goddesses.
Traditionally it is believed one can gain "boons" by repeating a certain deities mantra for a certain period or time or number of repetitions or until certain, specific signs appear. This is the origin of the idea that TM gives benefits in ones life.
TM, as a basic form of mantra meditation, simply leads one to elementary forms of mental quietude, while cutting one off from the surrounding world. Unfortunately, more advanced forms of mantra meditation or other varieties of meditation are not taught in TM or it's later techniques. This is probably why we only, after 50 years of people practicing it, still see mere relaxation response type findings, in even long-term TM meditators. In some cases, the habitual withdrawal or "transcending" can lead to psychiatric and psychological problems.
Meditation and the brain
Over the last several decades, many scientists have become fascinated with researching physiological correlates of the meditative state—studying Tibetan monks, Indian yogis and trained Western meditators as their subjects. One thing that has become obvious: different meditation techniques do not produce the same levels of relaxation, change in breath rate, brain patterns, or benefits for mind and body.
Unfortunately, you must be reading different science than leaders in the field are. It was long known (since the 1950's) that unusually high-amplitude gamma coherence was seen in Hindu Patanjali yogis who could go into samadhi, a higher state of consciousness, at will. One of the most "remarkable" things about meditation research during the 60's, 70's, 80's and 90's was that these finding were never replicated in westerners.
That is until recently. Advanced Tibetan Buddhist meditators who had mastered samadhi have been not only been able to go into higher, more integrated states of consciousness at will, they've been able to replicate the highly coherent EEG seen in Patanjali yogis! Samadhi it turns out is a common "skill" in even very different philosophical and religious traditions. It's no surprise therefore that this seminal finding was published in a major journal. It appears samadhi is a skill that can be acquired, with the proper instruction and with powerful enough meditative methodology, just like any other skill can be acquired (language, speech, writing, etc.).
For example, recent research on mindfulness meditation recorded a pattern of increased gamma in the rear of the brain, and found no significant changes in alpha activity.  Increased gamma is associated with heightened focus of attention.
Increased gamma coherence is common in advanced Hindu and Buddhist yogis. It is not found in TM practitioners.
Research on the Transcendental Meditation technique has repeatedly shown highly synchronous alpha throughout the entire brain, especially in the pre-frontal cortex.  Heightened alpha is associated with relaxed wakefulness, and increased coherence indicating improved overall brain functioning and is correlated with improved learning ability, higher IQ, better moral reasoning and increased neurological efficiency. This state of coherence is not found in ordinary relaxation or other meditation practices.
Actually the range of alpha coherence found in TM meditators is the same as that seen in normal humans, according to leading independent neuroscientists.
Meditation techniques that keep the mind actively attentive in the waking state, as mindfulness-type practices do, have not been found to consistently produce a level of relaxation deeper than ordinary eyes-closed rest—and relaxation is not a primary intention of all meditation practices. Transcendental Meditation is the only meditation found by research to produce a level of rest more than twice as deep as ordinary relaxation, indicated by changes in breath rate, skin resistance and plasma lactate. 
Actually TM is physiologically the same as napping. When using good controls (uncommon in almost all TM research), the difference is insignificant.
Though meditation can be practiced strictly for health benefits—such as reduction of high blood pressure—the awakening of full human potential, called nirvana or enlightenment, has historically been the goal of many of the venerated traditions of meditation. Fortunately, modern researchers have discovered a scientific basis for identifying higher consciousness—a coherent style of brain functioning and a balanced, more refined state of physiology. Numerous, peer-reviewed studies show that EEG coherence and more harmonious physiological functioning accompany both deep meditation and heightened awareness when stabilized in daily activity. Research breakthroughs such as these are raising the field of meditation and personal growth to the evidence-based standards of science.
Unfortunately basic meditation methods, like TM, do not exhibit any "higher" states of consciousness outside waking, dreaming or sleeping. While it would be nice if such things were true, independent research shows us that this is clearly not the case. After 50 years of the pop-meditation practice, no such higher states of consciousness have been found.
The mindfulness approach to enlightenment
Many contemporary approaches of mindfulness strive to attain enlightenment by recapitulating the qualities of the enlightened state as a practice in meditation and daily life. Equanimity of mind, being fully present in the moment, and impartially observing ones thoughts are some of the attributes often associated with the state of enlightenment. Many spiritual aspirants believe that consciously striving to maintain these "enlightened" qualities in daily life will lead to total mindfulness or enlightenment.
It's obvious you have little training in meditation, although I know you must be proud you were able to memorize some charts of mantras, and the religious ceremony to give them out at great expense.
This isn't even close to how enlightenment is seen or cultivated in Buddhist meditative practice! Another straw man Platonic fallacy.
Enlightenment through Transcendental Meditation
TM practice offers another approach to enlightenment, one that involves simultaneously culturing both mind and body through twice-daily transcending. By alternating morning and evening TM with one's normal, natural daily routine, the inner, silent state of "pure consciousness" becomes stabilized and lived in the midst of one's outer activity.
While this is an interesting and colorful claim by Mr. Ball, in actuality no such yogic states of consciousness, called turiyatita, are seen nor have they ever been seen associated with Transcendental Meditation! It's unlikely that they ever will. Repeated scientific studies have shown that TM is a simple, yet expensive form of relaxation response meditation, but that it does not lead to any "higher states of consciousness". The numerous side effects of TM, (which apparently is why the vast majority of TM meditators eventually stop meditation) esp. dissociation, depression and the desire to withdraw from life, are more likely what students of TM mistake for "witnessing" (a phenomenon desperately sought after by many TM meditators).
With this approach, there is no conscious attempt to maintain equanimity or detachment during or after meditation. The brain spontaneously becomes habituated to maintain a more orderly, coherent style of functioning, naturally giving rise to inner calm, broader comprehension, increased creativity and self actualization. When the physiology gains deep relaxation during TM practice, accumulated stress is dissolved and the whole system becomes more balanced and resilient, able to support the spontaneous growth of higher consciousness in a natural way.
This is typical TM teacher nonsense. Part of the reason TM has been so unsuccessful in working to integrate different states of consciousness into activity is believed to be because they ignore the prerequisites to samadhi. It is said that even if one meditates for hundreds of years, one will never attain samadhi if one ignore it's prerequisites. TM training does ignore these prerequisites so important in the tradition of Patanjali and in the Buddhist yogic traditions.
Modern day interpretations of meditation, often self taught and without expert guidance, can account for the differences in effectiveness between the various meditation practices.
Good point. Since there are no experts in meditation in the TM movement, only mantra-salesman, this should be considered a warning sign. TM teachers primarily are trained in marketing, memorization, pseudoscience, Neo-vedism and canned "checking" techniques to help see if the meditation is working. Unfortunately, not everyone falls within the scope of this "cookie cutter" and assembly-line approach to meditation checking.
When comparing meditations, whether the Transcendental Meditation technique, Vipassana, Zen, or guided meditation, it is now possible to refer to scientific research on the benefits before committing time to a meditation program.
Good point. Independent researchers have consistently found TM research to be both "poor", "exaggerated" and misleading. Such observations began as early as the 1980's and have continued up to the present day. The important element of honesty and integrity, hallmarks of good science and integral to actual scientific method have consistently been missing from TM Org-based meditation research. TM teacher training does not actually teach mastery of meditation, but a minimal subset of skills in order to be able to market, deceive and sell Hindu goddess mantras. Canned "checking" techniques (also memorized) are believed capable of helping students learn meditation.
Future posts will detail the science behind these claims, the opposing science and the references mentioned in this response.