I hate to play the pessimist, or cynic...however, Tom Rothman's statement remains absolutely true if a studio can submit two or more "cuts" of a film for the MPAA to review. If the MPAA gives one a PG-13 rating, and another an "R" rating, then Rothman can choose to release the PG-13 version without "making any cuts".
I am not sure if this is a possibility...for all I know the MPAA may only allow submission of a single "cut", which they will review and make recommendations/judgements. Does anyone know if multiple cuts of a film can be jointly submitted to the MPAA for review?