Poor/thoughtless positioning at roundabout give way lines.

[sussex2]

With learners there are two things to do IMO.
Overtake and leave them to their learning.
Follow at a respectful distance until the first option comes into view.
Plus as well and the same as with horses don't suddenly come into their vision from behind.

I remember when I was teaching ab initio being followed on a lesson quite closely by a car which went everywhere that we did more or less.
When it happened on another lesson with the same pupil I became suspicious. It turned out that it was the learners grandfather 'checking up' on what the pupil was being taught.
The grandfather had some individual ideas on driving which he must have learned from his own particular version of the Highway Code. A version that bore little resemblance to the actual code. He was checking that his grandson was being taught the way he wanted. The boy most certainly was not!
We needed a strong chat to resolve the situation that wasn't doing the pupil any favours.
I'd had the experience of being followed before but that was by the police when I was teaching the sons/daughters of one of Brighton's more 'interesting' families.