IME it is more an issue of who the points are crediting FROM rather than to.

AF/KLM are the absolute worst - I have never, ever had points post to CO, AS (and others, but mainly AS & CO) even when the FF# is on the BP. I ALWAYS have to submit my BPs to get credit.

The only other combination I've had an issue with occasionally is US posting to UA.

Apart from that, miles have always posted correctly without me having to do anything.