Teamwounding, and especially the revenge teamwounding vicious circle, has spinned out of control a long time ago. People hit each other all the time, and no admin can control that any more. Especially when people start revenge teamkilling.
Yes, people are supposed to only hit M when they think it was an intentional attack. People will figure that one out sooner or later. If not, we'll deal with it, because reporting people for the lulz is just as shitty as teamwounding on purpose. I prefer to have the servers free from both kind of asshats, so please take that as a warning.
About all the doomsday predictors: If you can't play one map without hitting a teammate for 5 times, you deserve to be booted for being a crappy and especially careless player. And no, it's not abusable, you simply can't make someone attack you 5 times. Feel free to prove me wrong.
(also, the kick is just temporary - when the system has settled, it will be a temporary ban)