"didn't the VC10 drink fuel like it was going out of fashion?? "
It did somewhat. And Boeing managed to get hold of an internal BOAC memo comparing the operating costs of the Super VC-10 and the 707 which stated that the Super had a higher sfc than the 707. Boeing immediately showed this statement to prospective customers with a comment like "Even the airline that specified it finds it uneconomic".
What they "ignored" was further information in the report that said that though the sfc was higher wherever a VC-10 operated alongside 707s and DC-8s the load factor on the -10 was about 20 pax greater which more that offset the higher fuel burn. Passengers loved it!