Dave. I just do not understand the suggestion that a single runway could move more traffic than two runways.
But that's not what I said.
I was referring to the movement rate
per runway.
segregated mode produces a lower movement rate per runway
Heathrow's two runways obviously have a greater
total capacity than Gatwick's one, but the
individual arrival and departure runways each have a lower movement rate (because you're not slotting departures in between the arrivals, and vice versa).
Sorry for any confusion.