scubadada -- I think you have totally missed my point(s):
a. The woman to whom I referred is my step-mother, not my mother-in-law (a very distinct difference). Guess what, she got her NAUI card in the late 60s or early 70s (can't remember exactly when) and WAS certified under "the old standards." As far as I know, she was never in a position to rescue anyone. The points I had hoped to show with this comment were: 1. Back "then" you didn't necessarily have to be a "strong" swimmer to be a diver; and 2. You don't have to be a "strong" swimmer to be a diver.
b. I didn't say I wasn't a good swimmer, I said I didn't consider myself a good swimmer -- a small, but very important difference because THIS WHOLE THREAD is about perceptions. What I consider a "good swimmer" is probably quite different from what most people consider a "good swimmer." This is probably why I could out swim a much younger former combat swimmer.
I believe it was Dirty Harry who said "A man's got to know his limitations" and that is very applicable to scuba. For me, the important thing is for me, and my buddy, to know "his limitations" be they swimming ability, diving ability, or whatever. As long as the dive I'm doing is within the limitations of all involved, that's all I care about.