The other complexity rules rule that out, though. If I have a password 10 characters long with at least one uppercase, one lowercase, 1 digit, and 1 special ch

The other complexity rules rule that out, though. If I have a password 10 characters long with at least one uppercase, one lowercase, 1 digit, and 1 special character then having one of those repeated won't make it any less secure. Rigidly enforcing that rule doesn't make sense, it's saying that "R%Vg9~\LL" is less secure than "R%Vg9~\".