I learned quite a few years back that arguing with a pilot over anything concerning the airplane won't get you anywhere. You've got to be professionnal, polite, and if the pilot looses his cool at you like they sometimes do and lacks good behaviour, just give him the released log book with a big smirk on your face and say "have a great day sir!" as you close the door exiting the flight deck. He won't know what hit him and will feel pretty stupid for loosing his cool! Try it, it works, been there quite a few times.