Does having a spotter unrack weight for bench presser aid lifter on max?

Answer 1

It's a good idea. It certainly doesn't hurt. After all, the bench presser has to work less immediately before an attempt. In a competition, any aid (such as a bench shirt) is welcome. (If you are doing a heavy single bench press at home, please always have either a spotter or two or do them in a power rack with properly set safety bars.)