Here's a concurrent discussion on doves:
https://www.thehighroad.org/index.php?threads/rabbit-dove-guns.853743/#post-11180254
The downside of a lighter gun in clays games is you get more felt recoil. While hunting, you don't notice it as much, because adrenaline affects felt recoil. The recoil is still there, but adrenaline's effects minimize the perception. It can also produce tachypsychia (the perceived slow-down of time), and auditory exclusion. I never heard the gun go off when I shot my first deer, for instance, nor felt the recoil. This is why clays games guns tend to be heavier than field models. Trap being the longest established clays game, has the heaviest guns. Sporting Clays guns are the most similar to field guns for two reasons; It is the newest clays game, and since Sporting Clays is supposed to simulate various hunting conditions, the guns tend to stay closer to field models, and more SC shooters use their field gun for it. In all the clays disciplines, you'll find the top shooters' guns are specialized for that particular discipline.
There is nothing wrong with using your field gun for a few rounds of Trap, Skeet, and Sporting Clays a year to hone your hunting skills. That's what the games were designed for. Just be aware Newton's law still applies. Lighter guns will kick more, all other things being equal. Trap is more for pheasant hunting, and duck, Skeet, duck and dove, Sporting clays, every type of hunting. If grouse and woodcock are your pursuit, find a club that has Helicé , AKA ZZ birds:
They simulate the flight of grouse and woodcock better than anything I've ever seen. Very spendy game, but great practice.