I do the right pocket/left pocket drill, too. Even with repeaters I sometimes want a different shell up the pipe, depending on cover.
As for confusion...... Many years ago my buddy handed me a 2 oz Federal 3"er in #2......he said: "just in case".....I never asked "in case of what?".
Anyway, maybe 12 years later we got into a pheasant firefight on a hilltop. Birds everywhere. I had my Ruger clays gun, reloading and shooting as fast as I can. Bird goes up in very thick cover, maybe a 25 yd shot.....gun doubled.....I about fell over. Dogs bring back two birds.......well, one bird in two pieces. Opened the gun and ejected one spent 3" Federal hull.
Sam