I have wondered about this quite a bit lately.
I am in the process of converting a Spanish 10 bore to a roundball gun and figured that this is how it would be done if I converted it to a muzzle loader, so why not in a cartridge gun?
The only thing is that I was thinking of patching the ball from the front and wrapping it down around to the wad side so the ball is completly wrapped. I imagined the ball leaving the cloth behind in the mouth of the case especially if the ball is seated in the shell mouth just up to midline using brass shells.

A nice khaki canvas or plaid patch would look sporty...

Is this really a concern? Probably not an issue if using a roll crimp in a paper or plastic hull.