[MITCHAY]

Sitting in the right lane for no reason
Pulling out in front when there is no one behind
Dive bombing form one lanes
Those who don't understand give way rules including merging
Slow acceleration after a stop
Tapping brakes constantly
Stopping for no reason or not timing it when you can see clearly what is happening from the other direction

With regards to indicating left exiting a roundabout, I don't bother when it is a very small roundabout and those with no right exit.

For dual lane it only makes sense if you are going straight in the right lane with right exit unless you can turn right from both.