I'm not convinced all crew know the minima, or they know but don't always like them. For example we regularly get crews asking for more time from intersections that are notified as the same for wake purposes. I do realise you can't ask every crew who operates in once every 3 years to know this, but when operating on single runway you really do not want that surprise after they've lined up in a gap which only gives you 2 minutes separation before the next lander.
Also less common is pilots asking for extended routings after certain aircraft, we all know the 757 is common to ask for more after but for example, A330 after B777 asking for 2 minutes for wake. There is nothing wrong with that at all (the rules clearly say a commander can ask for whatever they want and they will get it) but we need to know it before lining up (again, in the AIP).
Finally I've had crews ask for more time, which I've provided, and then say they're ready to go when less of that time is elapsed, which makes me wonder how they actually decided they needed more in the first place. Key here again being that as said above, we anticipate roll to time rotations. It is not a case that we start timing at rotation and can not clear you until the 2 minute have passed.
On the topic of wake, be aware that out of Paris it seems you now get new timings as well:
RECAT-EU, optimising Europe's airports capacity | Eurocontrol
Pair Wise Separations (PWS) / RECAT-2 | Eurocontrol