If I am that interested in the problem/solution I am also interested in discussing it. Answering the question straight and assuming good faith is a good way to open up that discussion. Even if they don't understand, there is still the chance that explaining it gives me a new perspective.

If I don't value interacting with that person, then I've already lost before I start. Communicate for its own sake. Enjoy the journey or don't bother with the destination. Expectations of being understood or being judged favorably just confuse the issue.

I understand why this becomes an issue, but I don't think it is productive to concern ourselves with such peccadillos. If these things become important, we might be starting from the wrong place.