I love the idea. And yes, I could see in a HUGE drop in getting physical from coppers.
I had a cop pull me over last weekend... licence plate light bulb blew out. "Hello sir, I'm John Smith with the XYZ Police department". super polite. no ticket. even joked around about the gun permit "I hope you don't pull that bazooka out, I'm only packing a 40 caliber here".
RagingBull, as far as a cop freezing up - I think veteran cops would drill the rookies harder on when to act, when to not act. If a cop worries about it a lot, he'll prepare mentally for it and know the law book 1000%. As it is, they wing it most of the time because, well, nobody is going to question them for it.