Importance Guernsey of a London Hub connection
The economy of Guernsey is now largely dependant on the offshore banking industry - hence daily flights to IOM and Zurich and the emphasis on London. The hub connection to give ready access to the City of London and facilitate connections to international flights.....USA, Bahamas, Bermuda and Middle East etc and other banking centres is seen as crucial to continued health of this industry in the island. International Bankers are prepared to link from Heathrow to Gatwick if a flight to Gatwick can't be obtained but would be unlikely to be prepared to traipse all the way out to Stanstead or Luton. Time is money to them and as a result would be likely to take their investments and business elsewhere.
As I wrote in my previous post airlines, have a track record on pulling out on this service and/or trading their slots to the highest bidder (See this months Air Britain News and the formation of a new concern "SlotTrade" by BA and other major companies to do just this) hence the islanders preference to have two operators on the route. This also has the effect of keeping the fares at a reasonable level for islanders visiting the mainland. Sadly the days of mass tourism to the island from destinations all over the UK are long gone.