From your comments I cannot make out if you are ATC, a Virgin employee or someone that is not 100% up to speed on fuel planning and the rules that go with it.
Nope not ATC, nor a virgin employee, and I'm fully conversant with the JAR OPS fuel planning minima, and the relevant CAA planning requirements required for the London TMA during "peak times of congestion"
Are you sanctioning that we all use the technique of calling Mayday every time we reach a minimum fuel figure at destination such that we avoid a diversion?
No I didn't say that.....and I am taking issue with your comments relating to "delaying others", and that you feel the guys on this occasion got it wrong. Furthermore, are you suggesting that the Virgin crew declared a Mayday to avoid a diversion? If so, I'd like to see some evidence to back that up.
Your statement also suggests that you would have considered a better course of action to be to head off to LHR (at possibly the worst time of the day) burning your diversion fuel..then declaring a MAYDAY due to low fuel.
IMHO, I would be happier to land sooner rather than later(at an airfield i can see is open and available), with more of a margin in hand..than perhaps to diligently follow a course of action that whilst legal in the strictest sense..is a reciepe for opening a can of worms, but then that may be a "cultural" or "organisational" difference between you and I Cuillin.
If he had any doubts about what he was letting himself into then he should have diverted en route at an earlier stage
I agree, but then neither of us were there....and the AAIB haven't seen fit to mention it..so from a regulators perspective, its a non-issue.