At the wedding at the end, the girl is wearing it again. And I was just 'OH GOD WHY ARE YOU SO STUPID??? WHO DROPPED YOU ON YOUR HEAD AS A BABY??' But at least the complete lack of sense was consistent with the rest of the episode.

He does at one point say 'I know you were betrothed to Robin Hood once', but nothing else. Like 'Also, you talk to him all the time'. It's just - sort of disheartening, because Guy really isn't that stupid. And it would make Marian's situation more tense if she was constantly under INTELLIGENT scrutiny, rather than just the old 'a nasty villain wants to marry her'. And it would intensify the struggle between Robin and Guy. But - it's not my show. Hmph >:(