Cases such as
Proof of no prime-representing polynomial in 2 variables
will cause the Accept Rate of the asker to decline even though there really isn't an acceptable answer to the question. What's a good approach? I try to make a point of accepting answers, and I feel bad about having my Accept Rate go down without being able to do anything about it.
EDIT: I ended up accepting that partial answer even though it does't add a whole lot of data. Regardless, I think the question still stands.