My Dear Ms. Friday,
I seem to recall that conversation, but I'm not sure of my specific answer either. However, I can answer that in the "here and now" (if you ever find the previous conversation, let's see how close I am!).
D/s, as I see it, is an outgrowth of a person's defense mechanisms. Sex (at least the way I view it, see Greg's opinion which is a bit different) ties into emotions at a very deep level. It is in these levels that many of our defense mechanisms are. A therapist will ask questions to make us see and evaluate those defenses, to see if they are still needed, have become destructive and should be removed, or may need to be modified. In a way, D/s is therapeutic for an individual who can't 'reach' those things any other way.
I encouraged my ex to get therapy. In fact, I STILL encourage her to do so, I am of the belief that she shouldn't be doing D/s with anyone, much less in a "Top" or "Domme" role which she's exploring now. She's going to hurt herself and those under her as long as she's not dealing with other base issues. D/s can be unhealthy, it can "mask" other issues.
However, for the right personality, and I have over two decades of experience in spotting these personalities, D/s can allow intimacy that guilt or other issues can prevent. Everything in a "vanilla" romance is in D/s, only carried "further" (including so far as to be over the top in some cases). I did my ex a LOT of good. No doubt the next woman who wears my collar will also gain self esteem, self-awareness, and an enhanced sensuality because I will demand it of her and not allow her to do otherwise.
I am, in some respects, a conscience. When she runs, I am a safe place. But I am also not a place to hide in, she is safe, and from that safe place she will be able to see what it is she ran from. And, with my help, she'll have to go and face it too.
This is part of the frightening thing about D/s: in the hands of a caring person it will make both sides change. I can't be "safe" if I'm not working on myself either. This is why I'm somewhat quiescent right now, I'm not strong enough to provide that structure when I'm grieving. It also shows that the Dom in a situation risks as much as the sub. I have grieved for our broken relationship over a year now...and I'm not done.
I'll take that beer any time, Ms. Friday. And I'll even walk you home. You'll never have been more safe since you left your parent's house.