Fair points on 'When ready' BOAC. And let's hope that they are taken on board and the word spread so that the service improves for all concerned.
On the other hand, I have had some (very very small %) pilots query the 'when ready' part with 'do you want us to descend now ??'. My normal reply is something like 'Negative, the clue was
when ready'. Must try and curb that kind of reply
The 500fpm is laid down as the minimum in the national document in the UK (AIP) so I don't think anyone in ATC can argue they expect otherwise. It actually raises an interesting point, which has appeared in a few threads. And that is that quite often we see ATC people claiming they expect to see different things from the standards notified in the relevant ATC and pilot documentation. For example people saying they expect to see a standard rate of 1500fpm (whose standard ?? it's not a published one). Or people saying that they are aware that a new level clearance cancels a previous restriction, but they expect the pilot still to do it. If they are basing separation on things they expect to see, rather than on the things which the regulations and procedures mandate, then I fear their technique is setting them up for a fall one day. There is only one way to be sure and that is to know what the procedures say, and if you require something different then positively specify it.
I agree wholeheartedly about the FMC gap. It is something I was looking at a while back but the project was overtaken by events. Perhaps it is well worth dusting off and resurrecting again.