what about the good old 'never perform a maneuver that makes other road users have to brake or change direction'?
the car was plain wrong to pull out there
the pick holes in peoples' riding posse is in full swing today
And wrong to go more or less the wrong way around a roundabout! Not even over the centre, if you watch, over the right side of the RAB, turning towards the path of the cyclist approaching from the right.
I don't see what's wrong with posting the vid - after all it doesn't say "Near miss, aggressive w***er nearly had me off" - it's merely an illustration of how drivers either fail to see or fail to consider, cyclists when negotiating junctions.
Neither does the OP "race up to" the car in order to do an emergency stop to make some point, but rather slows enough to avoid a collision whilst not exaggerating the avoidance causing anyone behind (should there have been, can't tell) to also become affected.
What's wrong with that.
"Well done" is also hardly "look out you f**ing w***er, I know where you live, I'll have you for that" or anything along those lines
All in all though, pretty much a non-incident. Which is good. Unlike the incident whereby a car doing the same, but later, sent a cyclist ricocheting off their bonnet and into my rear wing as I waited opposite the entry road of the cyclist. Caused by a driver failing to see or acknowledge a cyclist entering the RAB to their right