If in the above situation everything is "well in the grove" and the landing is uneventful I would just take the captain out for a beer and talk the situation over in full. If on the other had he is high on the glideslope and diving for the runway at 1800 FPM with the GPWS going off I will be livid, no beer, and we walk together to our Professional Standards Committee.I also will talk to all the other FO's and warn them to watch out for the behavior, if it persists we all go to the Chief Pilot's Office together.