"This should really be done with a black pen, not a blue one."
Had a similar thing said to me by a particularly anal antipodean checker...."ah ok" says me, the quick as a flash I "borrow" his Mt Blanc..Parker or whatever the hell writing stick it was to finish the plog, and then put a smiley face on it.
My other favourite one is being told to annotate "master COPY" rather than just " master" on the plog