Did I say that, Charlie? The shot is leaving the full choke faster, so I wouldn't rule it out.
But here's how one would test it. Take a choke-tube gun and have a second experimenter switch chokes in a psuedo-random fashion according to a predetermined rota and your task is to tell if in a set of twenty shots (ten comparisons) the kick is different. I've done some of that with powder charges one grain apart and I couldn't tell; the other tester couldn't tell, and my bet is no one can tell. It's hard for me to believe that the full choke can make as much difference as a grain of powder but who knows? This is yet another way to chip away at that art vs science difference in shotgunning you like so much. Science can answer questions like that; art can't.
I'll add this. I was POI testing last week and one of the guns was a backbored over and under. Compared to the singles I was testing, it was a vicious kicker. The stocks were similar, I don't know anything about the weight, but there was something there, something that the A/B test I described I think would come out as "different" to a significant outcome. I'll chronograph it when I get time, weigh it, change stocks, whatever it takes to find out what the difference is related to. By the way, the chokes are not particularly tight. So guns, as far as I am concerned, can kick differently, but I'm equally sure that there is a reason. That reason may be choke, may be something else, but it is something.
The reason I don't much worry who likes what I do is that I mostly just report the results of experiments and leave the explanations to someone else. Sure, I hate it when people try to change the subject, for example when I show two patterns are similar they tell me that if I'd measured shot-strings they would have been different. The have no more idea about shot-strings than Mr. Russell, but at least I think few would claim to be able to produce a "forward convex shot pattern" by tilting the gun.
All in all, I'll take my chances. Besides, as a few here have learned, I can "complain, and insult and deride" with the best of 'em.
Neil