Haleivi:
While I will grant that there are some who use such a limud zechus (see Radvaz ????? ??? ??? for instance) it seems pretty clear that the Rambam does not hold of such an idea. This can be demonstrated by the mere fact that the Raavad has his kashya on the Rambam. But the Lechem Mishna even says it explicitly: ?? ?? ??? ????”? ?”? ?????? ??? ??? ?????? ???? ???? ????? ???? ??? ?????? ??????? ??’ ??? ???? ?????? ????????. ?????? ???? ???? ?? ???????? ???? ??? ??”? ?????? ??????? ????? ????? ???