I think the first step toward evidence is being evident. You can find out how to cleanly include a link in your post by clicking Show Help to the right and below the box you type your comments in.
When you find a post you'd like to link, you can right click on the little links of chain below and to the right of that post and choose to copy the link.
From doing some searching, this thread contains at least nine positively scored comments I classify as mentioning the spoiler. here and here are representative examples.
Full list of the "nine": 6azo 6ar5 6amx 6al7 6as6 6all 6anm 6ait 6alr. Some of these are weaker than others, but the overall impression I have is that people have no problem writing posts as if it is a fact with no spoiler obfuscation.
The next discussion thread is here.
This is a new thread to discuss Eliezer Yudkowsky’s Harry Potter and the Methods of Rationality and anything related to it. This thread is intended for discussing chapter 84. The previous thread has passed 500 comments. Comment in the 14th thread until you read chapter 84.
There is now a site dedicated to the story at hpmor.com, which is now the place to go to find the authors notes and all sorts of other goodies. AdeleneDawner has kept an archive of Author’s Notes. (This goes up to the notes for chapter 76, and is now not updating. The authors notes from chapter 77 onwards are on hpmor.com.)
The first 5 discussion threads are on the main page under the harry_potter tag. Threads 6 and on (including this one) are in the discussion section using its separate tag system. Also: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14.
As a reminder, it’s often useful to start your comment by indicating which chapter you are commenting on.
Spoiler Warning: this thread is full of spoilers. With few exceptions, spoilers for MOR and canon are fair game to post, without warning or rot13. More specifically: