For a SS man, Kellerman is a shockingly poor witness.
A close reading of his testimony indicates that he thinks Kennedy is hit by the first 'firecracker' sounding shot and that the 'flurry' of shots came 'instantaneously' afterwards.
Yet somehow after the first shot Kellerman has time to turn and see JFK is hit, get on the radio to tell Lawson 'we are hit, get to a hospital', before the flurry of shots that supposedly came 'instantaneously' after the firecracker sound.
Makes no sense.
IMO, Kellerman only got on the radio after the fatal headshot, not before.
In any event, we can be sure that the elapsed time between JFK being wounded and his head being blown off is not 'instantaneous'.
Additionally, Kellerman seemingly assumes that the '4 wounds' to JFK couldn't have been caused by two bullets (each causing an entry and exit wound) and that Connally's '3 wounds' couldn't have been the result of one bullet.
Kellerman should know better.
When Kellerman is pressed to describe the 'flurry' of shots, it turns out he is actually describing a 'double bang' or the sound of something breaking the sound barrier.
Having said all that, the bottom line is Kellerman still won't commit to hearing more than 3 shots.
So the question remains, if there were 6 shots fired, why did most people only hear three ?
So far the answer seems to be one conspirator firing unmuted diversionary shots while the real snipers were firing away using rifles with silencers.