I was dead serious. As to your post, I believed it was an answer, in direct response the question at the end the preceding post:
And I didn’t read your answer all the way through, because I didn’t want to know. So I got it partly wrong because your response was not the answer that I expected. But still, by the very first rule, about nothing from other media, it was still a spoiler. As to my second quote in that post, by the same rule, Biggirl’s post was and is, unequivocally a spoiler. I think it’s reasonable to debate whether a post like that should be a spoiler, but by the terms laid out, it was.
And I didn’t appreciate being told to “shut up” by the guy who’s set the rules, already broken one of them and allowed someone else to break them without comment. Which is why I won’t be playing in that sandbox.