That's his problem not mine as I can't fly the aeroplane for him, or her.
At LHR where CDAs are the norm the compliance rate is very high. The most important thing for ATC to do is give the accurate track distance and update it if necessary then let the flightdeck manage the approach.
If it is obvious that CDAs are not being complied with then that's for someone else to take up with the crews, not me, I've already fulfilled my part of the bargain.
Personally I don't subscribe to the school of thought that says keep them as high as possible to the last second, or beyond, as all that is likely to do is lead to a bit of a rushed or unstable approach.
Good, accurate track miles and let the crew do their job.