Originally Posted by Monsieur Linguist
A low cost airline operating from LHR would be a bit of a contradiction in terms. That is why the most successful LCC's in Europe have created and expanded new airports close ot the metropolitan areas such as Stansted, Frankfurt Hahn and Milan Bergamo.
I appreciate almost all of what you've said but I disagree with you here, though I can't sight any definitive knowledge. STN and the other airports you've named aren't where most flyers, esp. the higher-fare paying business travelers, want to fly from. For those flyers, it's all about LHR and LGW; and then it's about frequency of service. And they'll pay more, usually much more, for the privilege. The lcc's have gone to the smaller airports by necessity, not as a matter of preference.