Nev, could you explain why you'd end up 5000ft high because of the A/C in front [going too slow?]?
F100 is 2 minutes in front of us on feeder time, but blocking our descent clearance. We can't do anything as any change in speed will mess our feeder time. So we are left high and dry waiting for the F100 to start descending and accelerate away.
It appears that the F100 flies slow in the cruise but then accelerates the descent to meet their time. Obviously if they are late on their time the more an issue it is for the following aircraft. I have had it a few times now, so it wasn't just a one off event where someone got their time wrong.