StaticFish wrote:

Excellent answer. Thank you very much. I thought it was something to do
with the spacing of trains running up the northbound piccadilly line. I
didn't think Hyde park corner was the line's controlling station (ie
Earls court for disrict) so why are the trains held and spaced and Hyde
Park and not Piccadilly (or whatever the lines control station is)

At a guess the point of spacing trains out at HPC is so there is even
running through the busy central london area. If they were spaced out
at Picidilly Circus it would cause chaos