You more than likely got those extra yards from the better compression of the angled hinge.
Jim,
No doubt, Angled Hinging results in less Clubface Layback (and hence more distance) than does Vertical Hinging. But, that is not the whole story here.
Try this little experiement:
Hit two full shots with a five-iron using Angled Hinging. On the first, stop at the end of the Follow-Through. On the second, complete the Stroke with a Finish Swivel. Determine for yourself which Stroke yielded the greater distance and report back. Thanks!
Threaded Mode
