Not really.

I bet other airlines have extended the flight time too to allow for the weather in winter.

The regulators (and media after passenger questions) would soon work it out and start to apply pressure on the airlines to reduce the padding.

"Why BA are you scheduling a 13 hour flight time when other airlines only schedule 11 and in actuality you also arrive in 11 hours..."


Plus it would affect the departure time of the return flight and the arrival back in LHR and where the plane gets sent next.