Sorry to disagree with 5mb but there's no way that I will anticipate an aircraft's descent profile. I will clear an aircraft for descent to the level specified in an RVA only when it is within that area or sector.
My reading of the good book (MATS Part 1 that is) supports this - it says that within the Radar Vectoring Area levels allocated must be in accordance with the
information published on the RVA chart. As far as I'm concerned I can't allocate the level until the aircraft is inside the area.
Yes, I may issue a clearance to cross some point not below FL X but it will be for traffic reasons. When vectoring that close to the field that type of clearance is more trouble to work out than it's worth. Clearly 5mb doesn't know me.
FWIW, in my view issuing a clearance on the basis of what the controller anticipates the pilot will do is not just poor practice but is simply asking for the controller to be proved wrong.
Clearly 5mb doesn't know me. Or maybe I've just been doing it for a bit longer and seen it all go wrong too often!