That's right. Let's say somebody replies to a post. Finds another post that's worth arguing against, and clicks on Reply again. Well now he has two posts in a row which looks like ass and it seems the mods are constantly merging them. Well then you could always use automerge. So instead of two posts in a row, it would just be one. The second post would be merged into the first. They would still be divided by a small "Edited:" that's written before merged content.