The results don't surprise me but I do think there is more than one way to have a thriving development culture. While not mutually exclusive, I think blunt/transparent environments are just as, if not more effective, than polite environments.

A blunt environment requires a certain level of professionalism but actively knowing you will be challenged when its called for and knowing everyone is simply striving to do whats best for the cause can be really refreshing.

I'm known to request that people tell me when I'm full of shit. I'd much rather have a moment of subtle hostility than a stretch of time where I operate under false assumptions. Once people acknowledge it's not personal, it allows everyone to move much faster.