I think in general a high cycling population promotes a higher level of acceptance but that does not necessarily decrease the amount of incidents. Having a higher percentage of cyclists is statistically bound to incurring a higher accident/incident rate . The higher level of acceptance is basically an aclimation thing. Additionally, there's a higher chance that the populace will know someone personally who is a cyclist and that promotes some awareness. Also, drivers tend to be a bit more on the lookout because deep in their mind, the prospect of hitting a cyclist could mean that the victim is a father, brother, wife, daughter, etc...