I'll change the thread to be more generally about writers.
If SPECTRE is a success, I predict a Purvis & Wade story and core script, with credited polishing from Butterworth.
Certain leaks implied P&W saved the script and EON owe them, although of course only they know what the relationship is like now.
I wonder how it must feel for P & W to always get called in because they are reliable - but then they get rewritten or polished by the "serious theatre"- or "Oscar"-writer.
Sure, it´s hard to get a script through on your own in the blockbuster business, and Bond will definitely pay well for them. But after "Skyfall" I got the feeling, especially during interviews in that time, that P & W were grinning through clenched teeth when journalists asked them about John Logan´s work. They also stressed that it was time for them to do something else.
It must have been very satisfying to be called back because Logan did not deliever. But to be polished again, this time by Butterworth... well, that must sting.
I guess if Mendes does come back for one final Bond film (no given) with Craig, he might reach for the same combination. If not - the next director will bring in his/her favorite to re-write.