Fit to fight I completely agree with, though I suppose that there are as many different definitions to that as there are styles of martial arts. But fit to fight does not always equal weight loss. I have gained about fifteen pounds since I got back into taekwondo three years ago due to muscle building.
I guess so, but the way i see it, is that SD/Patterns/whatever are our first line of defence (well second actually but Im ignoring enviromental awareness for the physical elements), now, as we are only human, there is a good chance that an altercation will go beyond that aka a fight, and the way i see it, though a fight should be over pretty quickly (with good training) one needs to be able to go, and keep going, at maximum for at least 5 minutes.. that requires fitness.. in turn, that requires hard work, which in turn makes you sweat, which in turn loses weight. Granted, not for everyone (eg. like you, theres a guy in my school who does weight training as well, so is building weight), but in general, with a reasonable diet, weight is lost IMO.
However, all that being said, some people lose weight more readily than others, myself for example, has stayed the same weight roughly since I started, because I have a fast matablism anyway and TBH, hardly any fat to lose.
Like I said, even though i think many would lose weight at my classes, I wouldnt use that as an advert, not cos its untrue, but simply because I'm not teaching weightloss and see it as a by-product of martial arts training - which is what I do teach.
Stuart