Aren't BA going to do some class of hopping sectors etc from LCY/STN. The STN aircraft are partially based in LCY. (so is there a major commercial issue - yes increasing rotations etc. but initially the airline would get to test the market).
For WAT - LON to work - it has to be double daily weekdays to compete against Dub/ORK from a business perspective. So allowing for 1.5 hour sectors X 4 plus an 30 mins on the ground in WAT/LON depending - you are looking at perhaps 4 hours gone on a morning and again similar on an evening. Maybe 7am to 11am - aircraft then tackles a European route midday and is back for the evening operation at 17.00 until 1900. (Which I think was pretty close to VLM's timings). Yield - well - Cork and Dublin close to departure days is not cheap. So surely there's a decent yield to be harnessed. So hopefully someone out there will give this a crack.
Regards
Shamrogue