Unless I am misreading this, no more than 3 full page scans from a particular book. So if you use three scans from Spider-Man #1, then that is it for scans from that particular issue in that thread. You can still post three scans from issue number 2 (which will then be the limit for scans from that book), then issue number 3 and so on. But, if what you post is being taken out of context, they will allow someone else to post the counter scans proving it wrong, they just don't want more than 3 scans coming out of one particular issue of a comic in general.
Sound about right @renchamp?
Say you use up the 3 scan limit and try to explain the context to someone who hasn't read the book. How are you to provide proof that that's how it went down?
This is not to say that if three scans cannot adequately show the point then the claim is false, it just means that everyone needs to find the book and find out for themselves.
So if you want proof, go find it yourself? That is tier 1 debating right there.