The history of the hethrow route has as many twists as the airport itself, Air Uk flew the route, then droppped it, Eastern Aw (Mark 1) picked up the route after protracted arguments with Air Uk prior to award of the route licence whom flew the annaugural flight with a DC-3. I know when the recievers were called in to Eastern in 84 the route was viable (Like the HUY to Esbjerg route)
as I have the route breakdown details from the recievers that was prepared by Eastern a month before its demise. Upon Easterns demise, Air UK again took up the route and with very poor marketing the route was dropped yet the Heathrow slot was taken up for another route.
Humberside to Heathrow was always popular till Air Yuck got its hands on it, the route was a vital link to the capital prior to the electrification / upgrades to the East Coat Rail Line.
Other attempts to resurrect a capital link have failed miserably, through no fault of the paying public who want such a route, the last I believe to try was CitiBus (Humberside to London City Airport) but failed due to the backers pulling out.
My point to all this, unless the likes of Eastern (Mark II) prosper the airport will always be a backwater just mainly catering for the charters in the summer and offshore helicopter movements. I just hope the owners can bring back some life into a regional airport that deserves better than when the council ran the airport.