I believe where the problem is that Continental and Northwest Fare classes do not match up. Otherwise, when you book a Q fare as a Continental codeshare on Northwest it translates to a V, L, T or K fare on Northwest - hence the 50% EQM. Now how is one to know this??? I dont know.

I purchased in January a Q codeshare fare on continetal.com and expect 100% EQM - like the website indicated when I booked.