It's okay, I agree with this. I didn't mean that his decision was smart, or wise. He puts his values before logic. But his case is an argument against a particular morality-based approach in the world of GOT.
I came up with this example, because I saw many fantasy stories where Morality is almost always good, and Self-Interest is almost always bad. In many cases, the "honor before reason" character turns out to be the Hero of the story, because the author thinks it's the right thing to do and because... Deus Ex Machina.
I think, GOT is an interesting example in terms of Theme, because it's not about black-and-white morality. Sometimes Morality leads to a good outcome (example: Jon's friendship with Sam), sometimes it's leads to a bad outcome (Examples: in the case of Eddard, or when Daenerys saves Mirri Maz Duur, who later betrays her). Also Self-Interest could be both good (Example: Tyrion's self-preservation) and bad (Examples: Sansa's selfishness, Joffrey's sadistic tendencies etc).
(English is not my mother tongue. So I just hope, I didn't make too many grammatical errors... )