Maths? Didn't realise I'd mentioned it. Because I fly from a mil field it's QFE on the instrument approaches, if I do an approach at Donny up the road it's QNH. I just think that even if they don't bin QFE altogether they could at least make approach plates standard and use QNH on all of them. I know that both QFE and QNH are on the same plate but why confuse the issue when there's no need?
As I said earlier once you're in the circuit you don't need the altimeter anymore, or shouldn't do at any rate.