IF full choke increases velocity over cylinder bore . . . then yes, there would have to be an increase in measureable recoil. Some people might notice the difference if that increase is as much as 40 fps, as Rocketman suggests.
Re overbore, I have a 1930's Sauer 20 that weighs about 5 3/4#. It's actually a 19 from the factory, so significant overbore. To me at least, it recoils less using the same loads than other, heavier 20's I shoot. Of course there are a lot of other variables at work there: different fit, good recoil pad on the Sauer, etc.
