j17
I don't think he's trying to
but making a legitimate enquiry,
unless I misunderstand you Expert?
If you're doing 300kt in the descent and are asked to slow to 220 we know you're ROD will reduce and should vector accordingly. It will take a long time to get rid of 80kt
and keep the same descent profile, probably longer than your intermediate approach will give you.
If the controller wants you to slow down quickly that should be specified in the clearance. A normal rate of speed reduction IMHO would be one that can be achieved by your aircraft type without use of speed brakes or resorting to level flight.