Ross May 20, 2017
First … you can do anything you want if it works for you.
Second … since we do not use the hands/arms to help*, your maximum rotation speed is as fast as you can rotate. Also, if you have maximized the backswing, and then use your maximum downswing rotation speed, you’re maxed out. I also believe your max backswing/downswing can change slightly at different times (not warmed up, warmed up and excited, tired at the end of the round, weather conditions, extra/less clothing like jacket etc.)
* It is very important to understand, if your hands take over or help, your body stops. You don’t get both … your body won’t turn and hit at the same time. A person swing an axe into a tree, will not keep turning his body and hit the tree with his hands throwing the axe, at the same time, he’ll stop his rotation just before the hands take over to hit at the tree. The body stops to take on a “supporting role” so the hands have something to swing against to throw the head of the axe. This action (stop body, throw club head) in golf, makes for a very bad golf swing and it not reliable.