Straight out of the book, eh Sunny?
The current "rules" are too broad; eg 230 at 20 then min 185 until 10 means somebody could come back to 185 at 15nm. There should be an explicit note saying "keep the speed up at the previous limit until you need to slow down". The speeds should be simplified as well: get rid of "160 at 10" and "150 at 5".
If there are persistent recalcitrants, have the chief pilots been contacted?