Shooting flying birds or clays with a flint, for me, demands a consistant lead - at least for a few feet, while waiting for the shot to go off - you know what I mean. With a cap-lock, I swing up quickly form behind, slapping hte trigger when the front of the barrel 'hits' the bird. This gives an automatic proper lead, for me with muzzleloader or with a modern gun. I don't look at the sights with them. With a flinter, I lead with the bead.
Sopping wet fibre wads, squeezed out then loaded, worked for me wth a capdouble for clays. We only shot 10 shots, though, but there was no change in fouling.