I have a 2012 defender 90 2.2 litre it doesn't do this. My old TD5 disco used to hold revs while changing and was a pain until I took it to get chipped in Adelaide the guys asked me how I drove the thing. Apparently there is a switch on the clutch that when depressed makes the engine revs drop. They put in a new switch and it was so much easier to drive.
Mike

