So I guess I should have explained it a bit better. We're thinking about loading the referenced quote right into the same place as the quote. So the user can tell if the "quoter" changed something when he quoted. Again we're playing around with idea so not sure how it's going to look or work just yet.

So just a quick mockup in my head would be, the user would see that a post has a quote. But in bright colors be alerted that the quote doesn't match the original in some way and given a button to load the original quote. The user can click the button and the quote is removed and replaced with the original full text. (We could even make that section resizeable so it doesn't take up the entire screen) That's sort of the idea I had in mind. My biggest concern is to avoid inspecting the quote text for differences since that CPU power could be used for other things. Character count is the first thing that pops into my head but isn't the most accurate signal of modified text. We'll figure something out though.

Also, this is good feedback so don't be afraid to point out something you don't like.