I think the real issue with that question is that it is too localized. Yes, it just happens to also be a yes or no question, but that itself shouldn't dictate whether a question gets closed.
You are correct that the policy on the Yes/No questions is not in the FAQ. However, there has been some discussion about Yes/No questions on Stack Overflow Meta (which, as few people seem to remember, serves as the unofficial FAQ for the entire Stack Exchange network - but that's a rant for another day). For example:
The general consensus is that Yes/No questions are ok as long as an answer can be provided that is more than simply Yes or No.
If someone can take a Yes/No question and turn it into something constructive and useful for future visitors, then I say go for it. After all, some people here have a habit of answering a question that is different from what was asked anyway.