When I had a pair of Vaqueros I spent a serious amount of time working up accuracy loads. For my guns, I was able to get better groups crimping on a lube groove such that the COL was more like a semi wadcutter and used light target loads of Bullseye in .357 cases. I reckon that the jump to the forcing cone was more of an effect than restricting case volume for my two guns.
The fellas at the range laughed at my “silly looking” long seated wadcutters until they saw how they grouped. You can’t argue with a tight group like that. It took a summer of fiddling to get tuned in. The fellas were in our club level bullseye league and showing up with a pair of vaqueros was a bit of fun as I had a custom bullseye 1911 as my “usual”.
Then I started wondering where all of this deep seating lore came from. I was stumped until I learned about the Smith and Wesson Model 52 that is widely reported to have other-worldly accuracy. Legendary tack driving accuracy- it’s a semi auto that shoots .38 special. Because of dimensions, the cartridge can be no longer than the .38 case. So... S&W sold factory ammo for it and it too was of legendary tack driving accuracy.
I felt no danger in increasing case volume, pressure can only go down until you are beyond plunk test length. For a pair of my single actions, my groups shrank significantly. Your mileage may vary!
Granted, accuracy from the Vaqueros never approached what I hear a good S&W target .38 revolver can do, but going long more than halved my group sizes. Theory is good, learning what works for others is good, but different guns are different when it gets down to the complicated details of bench rested accuracy.