See, this is why it's hard to capture a definition because everybody's opinion will be somewhat different. If we don't get a good one, we'll end up discussing completely different topics. It's like debates, you have to define your terms.
I suppose extreme in this case would be called "potentially life-threatening." But that's just me.
I think that that's a little different. There's a line between discipline, punishment, and abuse. I believe that would classify under discipline.