I second MAH4546s sentiments. In several ways, VS and BA are completely different operations. One of these is, as MAH pointed out, the fact that VS can fly low-yielding flights profitably while BA cannot. MCO is traditionally a very low-yield destination from Europe. Don't believe me, just look at the number of European charter airlines that serve the airport. Also, IIRC BA is using one of those specially configured 777s on the MCO route that feature only Club World, WT+, and WT, no first class. If it were a high yielding flight for BA they would certainly be flying either a 4-class or 3-class 777 equipped with First Class on the route.
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