A valid point Loosemoose, this makes the component courtyard even more important, and its calculation then depends on the method and equipement that will be used to remove a device, bottom terminated components being the most critical.
On the subject of courtyards, I have always used them as I deem them critical... I once employed a contracter who didn't, when I checked his board there were over 400 comp to comp errors. When asked how and why, he said he never used the courtyards and just placed components by eye... Guess what, he was out of the building faster than the speed of sound.
My point being, these things are there for a reason, in this case it is to make the board easier to assemble, there are to many PCB designers coming through who have not had experience of PCB assembly, or dont seem to think it matters, in my view this is wrong, we are designing a product that has to be assembled efficiently.