This discussion seems needlessly heated from my point of view.
Since I haven't actually heard it brought up yet, and I'm quite curious myself, I'll just ask this question:
guy b., how do you train WC and spar in a bare knuckle context? Are you able to do this safely, without frequent / serious injury? Or, are you rather looking for advice on how to do this?
I think that most of us can agree that gloves hinder some of what we do in WC to some extent or another, so it's not as if he doesn't have valid concerns. The question is whether or not he can apply his training methodology with an acceptable level of safety -- given, that level might vary between individuals.
I do think that variety in training methodologies and equipment used is essential, and I can see where sparring with gloves all of the time and catering your WC to that specific context will introduce unwanted tendencies. To once again draw a HEMA comparison (sorry guys!), just look at many Longsword tournaments. Because many of them are sparring all of the time with blunt swords and heavy protective gear, many of them have the tendency to fight as if they were using clubs rather than sharp swords, feeling that they must leave an "impression" on the protected man underneath to "score" a "hit," even though they're practicing Blossfechten (unarmored combat, for which there is a completely separate method from armored combat). So, rather than skillful bladework, we sometimes get some abstract clubbing match vaguely resembling historical methods. Armor and safety equipment, and even a "competitive sparring" mindset/context absolutely does change what we do if we let it and don't sufficiently direct and diversify our training.
The key, I think, is to balance your training methods, and stay honest with yourself and your training partners about what you're practicing. And, again, I don't think one needs to include "full force, full contact, full speed" sparring to be effective. You can simulate aggressive intent and pressure test your skills in a wide variety of contexts, with and without protective equipment, and come away with applicable and useful combative skills.