Trident , a lovely, but uneconomical aircraft .Seem to remember 10000 hp rpm on center for a/conditioning reverse on 1/3 350/365kt descent circa 16000fpm.
Useful if pushed but far from normal Ops.
More useful , the ability to descend and decelerate at the same time.
With respect to the PIA issue under discussion the 1000' gate should have given any 'professional' pilot the information he/she/it needed to make a sensible decision.