For those wanting central London the train is generally the best from Leeds, York, Bradford etc, but what the business community wants is connections to a London hub for international flights. I think BA would do fairly well with a 3 x daily Airbus 319 into T5. BMi Mainline and Regional have probably just about ruined their reputation with Yorkshire travellers by reducing services, starting some them stopping (Cork, LCY, Copenhagen, Lille (!) . How is it that Jet2 have overtaken BMi at Leeds in just a few years and have services to Paris, Amsterdam, Belfast, Barcelona, Nice --- routes that BMi should have started years ago.
BA or Flybe should now delevop a London route, it will take time and Yorkshire business travellers should get behind it and support it. Probably Flybe should also consider Edinburgh, Glasgow, Frankfurt before BMi finally leave the Yorkshire scene. Others would be open for Copenhagen, Brussels etc etc. And then there is EasyJet.... well that is another potential story.