If there was anything to solidly back up any claims of canon?

Except that it is such a subject measuring stick. For example, Zuko and Katara? Had WAY more subtext and hints that they (could possibly be) canon then Tonks and Lupin did.

But I get so pissed off at the canon/not canon debate because it comes with such a huge value judgement (canon is better) and I feel it misses the point (character interaction and potential character interaction.)