Indicating left...

[MontyVeda]

I suppose he could move over to the left to physically hinder any undertaking.

I was thinking this too, but was assuming the person mentioned in the OP was riding a motorbike rather than driving a car. The drive further up, U turn and approach from the other direction is an option, but not ideal (they'll be approaching a roundabout indicating right and people driving behind may assume they're taking the RH turn off the roundabout)... by the sounds of it, it doesn't sound like it's ever going to be easy.

@Arjimlad ...advise them to move house

 

[sheddy]

when on 2 wheels - hand signal
when on 4 wheels - hazard lights (not legal, but it might get their attention)

 

[Arjimlad]

He could actually do a life saver up the inside immediately prior to executing any left turn. Job done. It's part of the test, so all he need do is cast his mind back.

That's exactly what he does do, and he's finding too many twerps creeping up the inside of his indicating car. Hazard lights might be a plan...

 

[MichaelW2]

On two wheelers you usually have to swing out to the right to lean into a left turn. Moving left in the leadup may help but if cyclists can't read the road or the traffic, nothing is going to make them adapt to this situation.

 

[Ming the Merciless]

That's exactly what he does do, and he's finding too many twerps creeping up the inside of his indicating car. Hazard lights might be a plan...

Car or motorbike?

Are there any cycle lanes (white paint ha ha) running along this stretch? Some of the cyclists might simply be following a cycle lane or hugging the kerb as they are inexperienced. Roundabouts I take the lane, so wouldn't have this problem , and would be able to overtake him on the right.

Not sure what solution you are expecting other than do a second look behind before committing to the turn into the drive.

 

[MontyVeda]

That's exactly what he does do, and he's finding too many twerps creeping up the inside of his indicating car. Hazard lights might be a plan...

Thinking about it, that's what a guy up the road from me does... the approach to his drive is also the approach to a T junction, so Hazard lights demonstrate to those behind that he's going to do something other than turn left at the junction.

For your friend, maybe: hazard lights, stop, then indicate left, check, double check, turn.