I regularly fly with guys who accept "max speed to the field, cancel STAR speed restrictions" and are back at 210 or sometimes even 190 kias, with 20 nm to run, when the only regulatory speed limit is 240 kias at the IAF.
That, Claret, is because of training, experience and supervision. In the context of the current rather off-topic discussion here, this issue will increasingly drive the performance of aircraft in the system. Pilots and SOPs will become even more "conservative" as time goes on and this will further hobble the system, reducing it's flexibility and overall performance. Further, as le Pingouin mentioned, ATC are likely to add buffers to allow for the variations in pilot technique.
Yes I can see how Perth Airspace with Janadakot and Pearce makes it impossible to flow smoothly...
How LHR manage to do it with really busy Gatwick, Stansted and Luton in such close proximity AND lots of noise sensitive areas is an absolute wonder to behold!!
Either that or they just hope like hell..........
I don't like the belittling tone of your holier than thou post.....
Pot...kettle...black.