Interesting how the few posts I have read here clearly hold first officers in extremely low regard. Were you sky gods ever new? I am a new F/O on the A321 and have seen numerous errors by training captains, and gently "suggested" things regularly to muttered thanks. Reciprocal runways, incorrect STARS, gear up, GEAR UP, GEAR UP Please!, delayed Flap retraction, wrong taxiways, requesting FL ABOVE the Max, Missed FMAs, Flex detention for a G/A which is interesting for a few seconds. Never approaching CFIT or the likes, but worthy of raised eyebrows. We aren't just ballast you know.