- The wearing of pro team kit on a ride.
Who cares? Wear what you want, or not, as you like
- Deciding a stop is required (for others to catch up, route check, whatever) and then doing it immediately, be it on a corner, a hill, wherever, rather than coasting to the next convenient verge or pull-in spot. I have done this myself. In doing so I found myself annoying. I'm not a hypocrite after all...
I'll add a grumble about people who decide a regroup stop is required and then coast to stop apparently deliberately right on a junction or blind bend as if that's better than 40m or so before or after it.
I agree about the "Car up!" thing. Lately it seems to be yelled by the back of a ride, who single out when they shouldn't and let the car through to terrorise the front of the group in the midst of blind bends.
Yeah, it sometimes needs a quiet reminder that it doesn't necessarily mean to go single-file if the lane's too narrow to use secondary position but there's plenty of space to overtake when safe.
Actually, shouting "car up" at all is probably bad these days, with most CTC using it to mean a car's moving up the group and most BC using it to mean a car's up ahead.

So it's probably time to switch to "car back" (or front).
I have an acute disdain which when the following occurs I throw up some bile in my mouth it annoys me so much:-
I think I do all of those except champion stripes and H&H - hope you enjoy the taste!
And you do realise that most rear gear cables are slack in high gear? I think I've only a Shimano hub that is slack in low and I didn't have you down as a rider of those.