On Fri, 18 May 2007, Ray Saintonge wrote:
No, not at all - by analogy to living biographies, where we do need sources for facts being important, rather than merely documented.
Not in the same sense. We need sources as evidence for importance, but we don't require that a source actually say "this fact is important". Importance is something we deduce from sources, not something which must be explicitly stated in them.
You aren't addressing the question though. It was about the fact that a given fact is a spoiler, or that it does in fact spoil someone's enjoyment. The question said nothing about "importance" or "notability". Referring to these throws in red herrings for the sole purpose of having a question that was easier to answer than the one that was actually asked.
Uhh, you do know what an analogy is, I hope?
The point is that just like whether something is notable, whether something is a spoiler is a conclusion made about article content. Conclusions made about article content don't require sources in the sense of finding a source that states the conclusion.