First of all, I would just like to say "I told you so" about this thread devolving into this. Secondly, I present this video as evidence that it can be very hard to just "curl up in a ball and protect your head with your shoulder" in a crash. Sometimes things happen very fast and the forces involved can send you pretty out of control. I've posted this video before so I apologize if you've seen it already. Watch the guy on the outside of this corner. He is #329 and is wearing a blue and orange kit. He does his best to avoid the wreck but his back wheel gets hit and he is sent flying off his bike. When he hits the ground, his head is snapped back and makes pretty hard contact with the ground. If he had not been wearing a helmet, it looks extremely unlikely that his head would not have contacted the ground. He sent me a message after I put he video up saying he was fine and his helmed was broken and he needed a new one. Actually, just read the message from him and his direct quote was "My Giros Ionos helmet is trashed." So, that means the helmet absolutely absorbed some of the impact when it hit the pavement. Additionally, the helmet will prevent soft tissue damage/road rash on the head which isn't necessarily a life threatening injury, but it's a good added bonus. Anyway, here's the video. Best to watch it in HD.