Its unreal bro! You have no idea how deep down you can dig until you have no other choice. I can honestly say I was a changed man after that experienced. If that isn't enough, we get whipped and thrown by everyone of a higher rank. Most outsiders think it's pretty brutal, which it is, but it's a right of passage. It's called walking the gauntlet

http://www.youtube.com/watch?v=c3gsalP33pE

That's from one of my clubs gradings. UFC fighter Antonio Carvalho is in the video too, just look for the beard lol