Spitfire,
notwitstanding the fact that the southerly runway at Manchester is hardly ever open these days, bear in mind the following:-
On westerly operations at manchester, all departures have to cross the landing runway to get to the departure runway.
On easterlies, all landed traffic has to taxi across the runway being used for departures.
This is not ideal and inevitably slows the movement rate down. It does not happen at Heathrow, but some crossings do occur there due to the terminal geography.
Prior to the introduction of the second runway at Manch, 54-58 movements per hour was often achieved. i believe the record stood at 60 for some time.