I can see where that would be the case Jackb1. I look at it as a teaching tool. Yann says in his video to use this thing sparingly, for like 15-20 minutes and then switch back you your racquet. He says someting like, it's not about hitting really well with the SS, it's about hitting really well with your racquet. If you have a flaw, it seems the SS will exaggerate it.
Hit with it again today. I've been having some issues with my forehand lately. I've been hitting late, partly due to a pinched nerve (getting better) and the heat causing the ball to jump much more. Fore some reason, it was really easy to spot the problem and start to correct it with the SS.
Again, it's not the end all be all but it is one or many cool tools out there.
FWIW, Top spin is really hard with this thing..