Surely it’s not JUST about fuel burn on draggy arrivals...?
I think that we should bear in mind that the main aim of the Constant Descent Approaches into LHR, (which EVERYONE does - right) is to try and cause less noise in the London area.....?!(anybody got a link to CDA stats?)
PPRuNe can be a very useful medium by which to iron out little glitches such as type specific speed & configs, therefore lessening the occurrences of flap 20 gear down draggy/noisy approaches.