Gatwick Approach Spacing
In my experience, the final approach gaps (e.g. pack - minimum vortex spacing, alternate, 5 mile gaps or 6 miles after a Heavy) were always agreed between the respective Tower and Approach supervisors taking account of inbound/outbound demand and delay. Approach (TC) never just put an a/c on a 6 mile final because thy felt like it. The captain could always refuse of course if he/she considered the approach would be rushed (they rarely did).
Whilst the trial data shows missed approaches reduced by about 2 every 3 days, more a/c in the vectoring area on extended intermediate and final approaches would help to reduce holding delays that are measured by NATS.