So Howard Davies didn't know that there was already a EDI -ORD flight, at least in summer!
W16 there will be at least one daily EDI flight to NY. Both UA and DL drop 1-2 days, but different days.
PAX for other US destinations are most likely to use Reykjavik, or DUB, or even Schipol, which is no dafter than using LHR.