Once a year I shoot my sporting clays gun--a Miroku Charles Daly with 32-inch barrels--on a two-day charity preserve pheasant hunt. The stock is fitted to me and the long, heavy barrels move inevitably to the birds. It's almost impossible to miss with it.
Longer barrels are easier to shoot with, especially on any kind of crossing bird. Most of my hunting guns now have 28-inch barrels, which seems like a good compromise length. Of course, barrel wall thickness varies and two guns with 28-inch barrels can have very different balance, but in general they have a little bit of weight forward that makes them easier to shoot. In fact, chances are I will shoot a gun pretty well if I pick it up and it feels too heavy in the muzzle.
I have one featherweight, short barreled gun, a SKB 100 with very light 26-inch barrels that are closer to 25 inches in length. And, I hunted quite a bit with a 6-pound, 12 gauge, 24-inch barreled Benelli UltraLight when those guns were new.
Short-barreled, muzzle-light guns are great in heavy cover because they balance far enough back that they are easy to carry with your trigger hand on the grip while you fend off branches with your front hand. Most brush shots are going-away chances where there is not much need to swing the gun. Short-barreled guns are fine for that type of shooting. When you do encounter a genuine crossing target, you have to consciously put the barrel of a muzzle-light gun where it needs to go, which is difficult in the field and very difficult on a skeet field.
Short, light guns are faster-handling, which is an overrated quality. They are much less fatiguing to carry, though, and that can matter a lot. Speed with a shotgun is not a question of how fast you can move a gun, but how quickly you can acquire the target with your eyes, and whether you can trust your eyes and hands to make the shot without you trying to double-check and make sure regardless of the length of your gun's barrels.