[whip]

Agreed, you can't have a constant hand speed and a constant acceleration rate of the hands at the same time. It's a balance, a very fine line. Obviously the ball will slow the things down, I don't believe it's right to try and speed up through impact, there are many factors involved in this, lever extension as mentioned cf, mass, sense, over-acceleration, power accumulators, etc. Acceleration rate is not equal to lag pressure just because lag pressure is a product of acceleration rate. You can have club head acceleration with constant hand speed.