Let me preface this by noting that I know nothing of Megirot personally, but just impressions from what I have read in articles and blogs. And there is no real reason you should really care about my take over that of anyone else. However, I do have some thoughts about it. And since I posted Yehuda's comment last week and mentioned that I might try to explain what I agreed with and disagreed with, this will be part of my attempt to follow through.
In this post, I will try to put forth the reasons for Megirot, though tempered somewhat. Perhaps in a later post I will elaborate on the possible causes for concern.
I think that to a large degree, the concept of Megirot is silly. It is pop-psychology by people who are not trained psychologists. And it is masked as religion, and specifically Jewish religion, but it is really folk-religion with a Jewish tinge, guided someone who is not a professional member of the clergy. So there is what to worry about. If that declaration runs afoul of the laws of lashon hara, so be it. I will try to elaborate on why I think this later, bli neder -- perhaps in a different post.
However, there are people in need of help. And I recall a research study in psychology that compared different therapy methods -- e.g. Freudian therapy, Rogerian, Gestalt therapy, etc. -- I am giving examples not from memory, but rather making up the specific examples. But the most important factor in success was not the particular method, but rather whether the therapist believed in it. Now this could be because those who believed in the method were more likely to be effective in applying it. But I think that one should not dismiss the relationship which develops between the therapist. And if the therapist believes it will work, and is committed to it, this will be conveyed to the patient. And the bond with another human being is good to improve one's emotional and mental health. Call this a placebo effect if you will, but this is an actual psychological effect, and its benefit should not be dismissed.
Referring to Yehuda's particular case, as representative of many other cases I am sure exist. Raising 8 children is hard, as this cartoon illustrates:
This can be quite a burden to place on any person. Especially if money is tight as well, as seems to be the case. And post-partum depression can also factor in. To have to look after the kids, clean the house after all these kids, prepare meals, worry about money, etc., with the possibility of more kids on the way when you already cannot cope, is something that most of us cannot really imagine.
Such a person needs a support group, or a therapist, or something. At the least, a book club, to make friends, vent, etc. Or a support group of people going through similar things. Or a therapist to whom one can express and explore one's feelings and psyche. But what are the possibilities of this in a chareidi neighborhood. I don't know, but I would guess slim. Going to a psychologist might bring on stigma that could make it difficult to marry off those 8 kids. Hanging around discussing novels? What a waste of time! Is that something a righteous Jewish woman would do?! Perhaps she could join a tehillim zugging group, or a challah baking group. Or -- one could practice Megirot and go to Megirot groups.
The beauty of Megirot is that it casts itself as a religious activity. One transforms the mundane into the spiritual. And thus one prays, saying "Ana Hashem..." before cleaning any drawer. One goes to a spiritual advisor. And by making use of Jewish or Jewish-sounding concepts, it sounds like a religious activity. And this religious garb is good because it provides an opportunity to women who previously would not be able to participate in it.
A prayer to Hashem might be said before cleaning a drawer, but the important aspect is not the talking to God, but the talking to oneself. This is introspection, and thinking about what one could or wants to change about one's life. And this takes what would otherwise be drudge work, or an overwhelming task for an overworked mother, and turns it into a reflective, transformative experience. This is good.
Further, one attends classes with other women who are going through many of the same problems, and who sought out megirot as a result. This provides a sense of community and a sense that they are not alone in their struggles. And talking over, and preparing "prayers" with a spiritual megirot advisor is a form of therapy.
Of course, in many cases, it is possible that these amatuer "therapists" do not know what they are doing, and can thus unwittingly influence vulnerable people in negative directions. And the focus on the ideas and personality of one perhaps troubled individual can lead one astray. And there is a problem of the (unwitting) coopting of religion for this end, which together with many other things can move the practice of Judaism in a direction it should not go. It is part of a negative trend and may be somewhat cult-like. Even though it might not be avodah zarah, it may be problematic to have such a set-up in the general case. Though for an individual case, if someone's sanity or emotional well-being is dependant upon it, even I might say that one should do this.
This post was meant to argue in favor of megirot, though I think it is balanced. If I get around to making the next post, it would be an expansion of what I only hinted at above -- e.g., why I think this is folk religion, even if every idea can be found in sources; the ritualization of mundane activities, because of the present restricted role for women in ritual Jewish life; and why individual warning signs should be made public, even if a strict reading of Shmirat haLashon would indicate otherwise. No promises, though.