LHR route loss
There are a lot of pro's & con's involved here (many of which have already been covered in some detail) but I think it really will always depend where you are beginning & ending your journey certainly within c.200-250 miles of London. If it is more convenient (as in my case living less than half-an-hour from LHR) then it will be my first choice to fly BUT if my destination elsewhere in England is not really near a direct airport connection then other means inevitably have to be considered.
In the the Durham student example above, I am surprised in his choice as he could quite easily take the train direct to Oxford & his journey time would be just over 4 hours. Assuming (as he's a student!) he's using public transport connections at both ends of his journey then unfortunately going via LHR isn't any quicker. In fact I would estimate his total journey time at around 5 hours (& that's on a good day on the M25 using the coach connection!).
Don't get me wrong I would like to support as wide a choice of destinations as possible out of LHR (after all it's in my interest!). Unless you really need to connect to another flight via LHR in which case NCL at c.50 miles up the road from MME is really the only way to do this then I'm afraid it's trains or cars from about a month's time!