Most of the witnesses that claimed the shot came from the "grassy knoll" were badgered by the investigators with questions of "could it be an echo?". Well, of course it could have been an echo!
Those that stated that the shot came from the TSBD didn't get asked.
I think the curb chip and wound were from a shot that went through JFK and then bounced off a thing or two.
That's where it falls apart (see my #344). The "magic bullet" went thru JFK, then into John Connelly; then later was recovered nearly intact (note: it was not "pristine", but somewhat flattened around the lateral).
According to the WC report, the "head shot" fragments could barely crack the windshield; much less travel another 200+ feet and take out the chunk of concrete that injured Tague.
Nearly 75% of the weight of the "head-shot" round was recovered inside the car.
So:
1 round -- curb/Tague
1 round -- Kennedy neck/Connelly wounds.
1 round -- Kennedy head shot.
Anything else means the brass count was false
--or there were more than 3 rounds.