Just thought I'd post this after seeing the bottom Phil Cheetham graph.
1.If you look at the green graph it shows the lead wrist velocity in the extension direction at impact is approximately 350 degrees per second.
2. If we assume average pro golfers have driver clubhead speeds of 110 mph at impact, which then reduces approximately by 1/3 post impact to 73 mph.
3. 73 mph is 1285 inches per second.
4. Let's assume the clubhead moved at 1285 inches/sec for 10 inches post impact , how much time will that take?
1285 inches is equivalent to 1 second
10 inches is equivalent to 10/1285 = .008 secs approximately
5. Next assumption is that clubhead impact will ball will have no effect on the lead wrist extension velocity of 350 degrees per second during this .008 secs.
Question: How many degrees will the lead wrist extend in .008 secs?
Answer: 350 x .008 = 2.8 degrees
Therefore for a clubhead moving at 73 mph post impact , the lead wrist will only extend 2.8 degrees approximately over a clubhead travel distance of 10 inches (which I assume is approximately P7.2).
DG