davehir: Do you use the whole of a players completion record or do you use say the last 25 competitive games.
AFAIK it's the last 100 MP games, excluding A/S.
Quickest way to recover - as proposed here - is to play some quick&dirty Blitz with a reliable partner and reliable connections. Prepare for 30 to 40 as an example.
After the introduction in 2012(?), they first showed the numbers but soon changed to the traffic light buttons - apparently, too precise information would confuse their clients(?) At that time, random discons were not as much an issue as they are now, and it appeared weird to me that the company would decide who should be bullied and who shouldn't for something supposedly neutral like "completion rate".
Now, IMHO, the red stigma serves in part to bully players for issues outside their control, while MP games have lost much of their attraction.