Talking of Zurich - I have operated through there a couple of times and they have a simple system - the board in front of the aeroplane gives you slot time and start up time in order that there not be a queue at the hold. Started on the time, taxied out - no queue but there were lots of aeroplanes departing and arriving.
So, the fault lies with the ground controllers - yes, they should take the blame, ineficient squanderers of the earth's resources - that's better, shift the blame from the drivers to the controllers
