I also think clones are a pretty weird concept.
Clones in vanilla scenes would only make sense for one single type of scene, a threesome/foursome with the same girl, but that's it. In all other cases I think everyone'd rather have sex with the real one.
And it would be pretty contradictory to have netorase scenes with clones. People who dislike netorase would still avoid those and people who enjoy it would like it less, since the LI wouldn't actually be shared and have sex with another man. At least in my case, I love netorase and clones would defeeat the point, to me at least.
Of course if it's nothing but an option where you can choose to either have the actual girl stare in the scene or one of her clone instead then there isn't really anything wrong with it. It would only become weird if it ended up being forced upon the player.