This is probably a silly question ........
Having had the odd jump-seat trip (pre 9/11) with an old mate doing bucket and spade runs in a 757, they consistently turned it round (or a bunch of Manuels or Stavros' did) in < 45 mins.
So why does a VC10 take 1.5-2hrs? Nothing to do with the (excellent) seat pitch surely BEags??