How would you like to feel no pain?

I just read an about me and post from a blog called Memoirs of a Grasshopper. Great stuff. I'll quote some extracts from the post: What's to Gain From Pain?.  My advice,  go read the original....

Have you ever wondered what it'd be like to be impervious to pain? As a martial artist, it'd certainly have its perks. It's the sort of superhuman power that belongs in comic books. Amazingly for some people it is a reality.

Congenital Insensitivity to Pain with Anhidrosis CIPA is a rare condition in which children are born without the ability to sense pain .... They are normal in every other sense. ...Children born with CIPA have no protective reflexes...Pain is the best instructor, but no one wants to go to his classes....