JohnSnow said:Wow...just...wow.
I'm going to restrain my personal opinion of how well the SCA fighting style simulates real swordplay and point out a few things:
Heh. Should known I'd have pulled an ARMA grognard out of the woodwork with that comment.

My definition of "best" might be a little too particular. I was attempting to say "the system of mideval combat gaming/simulation that the most people reading have a chance of being personally familiar, veers close enough to simulationism to be at least marginally accurate, and has been tested enough to permit some wacky things to happen." Which is to say, not great, but acceptable. SCA combat is what it is, which may or may not be completely realistic, but is as realistic as most people are willing to have and still have fun.
Health of combatants, armor, and all the other issues your bring up are too general to make assumptions about. I'm not at all positive that medieval warriors were in better physical shape than your average SCAdian. Leaner, most certainly, but fitter? Considering the diet and general level of health at the time? Debatable.
I'll point to the best example of a "real life" one-on-one medieval combat I've got in my library: The judicial duel between Jean de Carrouges and Jacques le Gris in 1386. (The Last Duel, by Eric Jager. Excellent read.) At least one of the combatants in that fight was getting over a very high fever. The winner's masterful dueling technique was to grab his opponent by the top of his helmet, step back, and yank him prone in an almost Stoogian maneuver. The fellow couldn't get up in his plate mail. Nor could his opponent stab him with his sword. Eventually he pried a visor clasp open and shoved a dagger into his brainpan.
SCA, ARMA, D&D, I don't care - nobody's going to try to simulate that one.
In any event (and to drag us, kicking and screaming, back on topic) - D&D combat is going to be its own animal in the end, and only look as real as is tolerable. I still think that pushing your opponent around on the field is going to matter much more than we give credit for.