I can understand that there is an increase, but double?
That's the math, Weightshift. If you've got a hundred-mile trip, you can drive 50 miles per hour for two hours or 100 miles per hour for one hour. But if you decide on the latter, better watch for cops! The same is true when you push your Golf Stroke to its limits. Overacceleration is indeed "the menace that stalks all lag and drag."