Actually Rocket - IMO - the incredible increase in arm injuries cannot be attributed to only one cause. I agree.
I think it would be statistically impossible for that to be the case.
Given the exponential increase in youth baseball players arm injuries in the last 10 years - it is reasonable to assume that there has to be multiple causes.
IMO - One factor that must be included however - is the use of the curveball at younger and younger ages - as well as the frequency of such use.
Thats the easy part to figure out. The more interesting part to me is - Why?