I have searched the internet high and low to see any pitching video that shows a "rise ball" that actually lifts up (jumps over the bat, rises up, curves upward) off of its original plane of trajectory. I'm still searching? As someone on this forum pointed out, once the ball leaves the hand it starts losing speed immediately and is subject to the effects of gravity and drag making it impossible to generate enough lift to overcome the effects of gravity and drag on the ball. I'll say it again, every thrown ball has a parabolic curve to it, whether you are throwing overhand or underhand. Is a "rise ball" still effective, YES, because it does not drop as much other pitches the batter sees. Period.