I just don't get it. Those who "claim" lane splitting will reduce rear end collisions, due to inattentive cagers. This places ALL the onus on the cager to be attentive. As Roomie stated if a rider leaves proper space between them and the vehicle in front, AND THE RIDER IS ATTENTIVE then there should be no rear end collision as the rider would see the vehicle behind isn't slowing and take their escape route to avoid the collision. Both of these principals, (leave space and have an escape route, are covered in the MTO motorcycle book). If a rider can't recognize that a vehicle approaching isn't slowing then they shouldn't be lane splitting either as they must have an issue with depth perception etc. So they rider should be EQUALLY at fault for the collision as the cager as they too should be attentive.
"As for the videos of lane splitting collisions the majority the bikes are traveling at ridiculous speed differential to the surrounding vehicles. It would be ludicrous to write a law which states the bike must not exceed more than say a 30 km speed differential, that would be UNENFORCEABLE. How is the cop supposed to gauge it, not like he can get a radar reading on surrounding vehicles and the bike at the same time. Even IF they could determine it, how do they pursue the offender. So that suggestion is mere fodder in an attempt to gain support. The rear end collision videos don't show if the rider was attentive or not as most of the cameras are bar mounted and don't show what the rider is doing pre collision.
Having said this I was rear ended last June by another bike. I was being attentive but the bike was weaving in and out of lanes and came into my lane at approx 100 km/h a mere 2 car lengths. So I had no time to react, (BUT I did have enough room from the vehicle in front that I was to keep my bike up and not rear end that vehicle), so yes there are still going to be some unavoidable collisions but these are likely to make up a very very tiny percentage of collisions.