I don't entirely agree with that. Sexuality is more complex that a simple label, and more fluid. We are all capable of atypical behaviour, some people more than others. There is no need to read too much into attraction to a person/gender/type/whatever outside your normal interest range, whether or not you act on it.

No one freaks out if they're in the mood for wine instead of beer once every few years. Why should sexual attraction be such a big deal?