Originally Posted by MudhammedCJ

Trying to do everything the captain (or FP pilot) normally does before he does it. Examples: turning on the anti-ice if he's not flying the leg, arming the speedbrake for landing, searching through the logbook when arriving at the "jet," turning off the center tank pumps instead of just pointing them out if the tank is just getting empty, making PF calls *every* time while performing PM duties, making up new calls that aren't in the big book of knowledge, actively searching for minutia to write up in the logbook....

One or two of these things here and there and I don't even blink an eye. When it's a pattern of single pilot kernal douchery, it makes an easy trip downright loooonnngggerrrrr.

Blaring crappy music or crappy sports at the gate between legs... the list goes on and on. Just as many hard to deal with FOs as captains. Fortunately it's still a small percentage.