What you're suggesting regarding the GFCI protection for a fan over a tub or
shower, is only acceptible if he's wiring one bathroom entirely on a 20 amp
circuit. If, as he suggested,he feeds *multiple bathroom receptacle outlets
with one 20 amp circuit, no lighting, fans, or anything else, except other
bathroom receptacle outlets can go on that circuit

Correct. I was assuming he was running 2 seperate feeds for each
bathroom.