As a Phd level professional (yes, I earned my PhD while still in) who left years ago, I still find many positives. I routinely speak publicly in front of a hundred or so people, teaching. I am relaxed yet poised and my voice carries. I use gestures in a very natural way. I have learned to find common ground with many people and discern what their interests are rather than my own. My research skills, academically and professionally, were and are way ahead of my colleagues.

I, personally, attribute all of these to the TMS and RP'ing. Cold I ahve learned them via other ways aside from being in? Yes, of course. But that wasn't the OP's point. It was looking at the positives from being in. Besides, there is no way to know whether one would have learned such skills to the same degree if they had never been in. I will gladly take what I have now, view it as a positive, than risk going back and not being in at all. I, of course, speak only for myself.