Why would they be slagging off 4 engines when their whole fleet would (until then - if they do but them) be 4-engined aircraft. That's just like saying 1 of their planes are good, the others are rubbish, which isn't good advertising. I doubt that VS
would buy the 777 but if they did, i'm sure that they wouldn't be putting any slogans on them regarding the aircraft type, maybe something completely different like "Fly a Younger Fleet" for example. Otherwise it would just be hypocritical.