as what you DO feel is the slide hitting the back of the frame
I don’t quite follow that statement.
Since the same force be it the round firing with the lock or without the lock stopping the slide it’s the same impulse on the gun and the hand ether way. The only difference would be the action of the slide going into battery.
Also the fact that the bullet is well out of the barrel before the hand has reacted from the recoil and the slide has not completed it travel locking the slide or not wouldn’t make any difference.
I shoot a lot of 1911’s and with the same round they all are different. My gold cup is like shooting a pant ball gun yet the same round in my Kimber Royal is brutal. But it’s not the round it’s the fit to the hand. The Kimber is short and doesn’t fit my hand that well but I don’t mind since it’s so easy to carry.
Of all the guns I have shot over 40+ years the only gun that I found uncomfortable to shoot was an S&W 19 with the small grips. 6 rounds and I never wanted to shoot one again. Set of Pachmayr’s and it was comfortable.
Again as so many have said, it’s not the round or gun, it’s the fit to the hand.
"The difference between stupidity and genius is that genius has its limits" Albert Einstine