Since golf balls behave in {TAIL ~ a linear viscoelastic fashion}, {HEAD ~ inbound ball velocity} is functionally equivalent to club swing speed 
Since golf balls behave in { TAIL ~ a linear viscoelastic fashion } , { HEAD ~ inbound ball velocity } is functionally equivalent to club swing speed
OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH