It seems its an argument I cannot win - the guy has had an advanced driving instructor tell him that left lane is for left and straight on, and right is for u-turn only, and that the lane markings can only apply to first roundabout only.
I'd disagree with that on the basis that they are linked mini roundabouts so the markings apply to the complete junction 
Certainly a similar situation in Ipswich is treated as one junction WRT the markings but each roundabout is treated separately 
the counter argument is, according to this chap, each should be treated as entirely seperate things...
My understanding (right or wrong), and the way I would approach it from a HGV point of view, is that the roundabouts are treated individually but the junction as a whole from the road marking point of view.
Had to navigate a similar type of junction as part of both my HGV and Bike tests and treated as above (and how you would by the sounds of it
) and passed both with no minors/observations for road positioning or junction navigation 
I passed my 1st car test and 2nd bike test with no minors mentioned to me

I failed the first bike test by putting a foot down on the U-Turn - when we got back, the examiner chatted to my instructor, who then said I was a ****ing idiot, as the examiner had told him "I had pissed the rest of the test perfectly"

(which I think gave me the confidence to carry on with it (it had been a stressful DAS course, with the other rider (who also failed the test) having fallen off at 60mph and ended in a ditch - but fair play, still turned up the next day)).
Obviously, learning to drive/ride to pass a test is entirely different from learning to drive/ride properly, as I'm sure those who have done advnaced driving courses will agree...