If Longstreet had made sure to commit... (if) Stewart been successful...
One more 'if':
If the cannonade that proceeded Pickett's charge had found their target, instead of missing with overhead shots that did little damage.
Right. Another IF.
I still think that if all the ifs played out right he would have won and Lee had a reputation of being a gambler and hard fighter on the battlefield.
the reason the reb gunners were over shooting their targets was because of the fuses supplied by the Confederate ordnance dept. Until the late spring of 1863 all fuses for ANV artillery came from the Richmond Arsenal. The fuse manufacturing facility blew up in May. CSA ordnance ordered another arsenal further south (Selma, I think)to supply the ANV fuse needs for the invasion. the other arsenals fuses when cut to the same length as the Richmond fuses actually exploded a couple of hundred yards further in range. The CSA ordnance dept. did not discover this disparity in fuse performance until after Gettysburg.