John,
I actually believe it can be done; and, honestly, I was surprised when I didn't see the effect when I filmed some of the videos linked above. When we hit some of those shots, I was convinced that the OB was curving after coming off the cushion. However, when we looked at the video later, we saw no curve (although, the OB was definitely being "shortened" or "held up" or "firmed up" or "twisted" a significant amount, which is most definitely useful in actual play).
Concerning needing a "good enough stroke" to hit a particular shot, I would be happy to accept the following challenge: Post a video clearly showing the OB curving a significant amount after rebound. If you do, I will also post a video of my best attempt to perform the exact same shot. I might not be able to execute the shot on the first attempt like a world-class professional like you, but I am confident I can duplicate any realistic and practically-useful bank shot that you can post, assuming the equipment conditions are similar. If I can't, then you will have conclusively proven that I "don't have the stroke" necessary to create the claimed post-rebound curve effect, and I will be more than happy to admit that I have an obviously weak and inadequate stroke.
Regards, and with respect,
Dave