I think it would be pretty dumb of anyone to argue the case that proper thought out weight training would not benefit the karateka. I agree with Susan here, there is way too much bull**** in karate and martial arts in general. All this samuraii spirit and ki rubbish is, I think, best kept in comics. Karate is hard enough as it is, without delving into the realms of fantasy and mystical powers. Keep to what you can see and feel.
Guy B's problem seems to be a motivational one. To succeed at anything, be it sport, academia or whatever, means that you have to make sacrifices and do the "boring stuff". If you are not willing to make these sacrifices, then perhaps you lack the "mental toughness" required??