Well, hanging upside down by your ankles while singing "American Pie" might help prevent injury, too. There's just no reason to think it does.
There's plenty of reason. I had an imbalance causing me to twist to the left, core exercises have helped me correct that and now i ride A LOT more comfortably regardless of power. Anything that can make you more comfortable in a sport with 200+km races is dam useful.
I've been using free workouts from a website called www.coretrainingforsport.com. The workouts are really good and have helped me get rid of my back that I used to get from cycling.