Re: Weapons training leads to good aikido.
Let's approach this line of reasoning from the opposite direction then:
Why does body art NOT (or tend not to have) have this violent dynamic (occasional bonks and raps that come and go with no mention; primal instincts of self-preservation; etc.)?
For me, I always try to have this stuff in my body art - just like in weapons. If it's not there, it's because I'm working with a beginner that is on their way toward such training. Otherwise, it's there, and I've never felt the need to say, "Man, this is so "lite" compared to weapons training." However, that is what a lot of folks seem to be saying here. If that is the case, aren't we saying more about how we train for body art than how we train with weapons?