You're reading along in a thread and all of a sudden everybody's quoting the object of your disaffection. May as well "unignore" the s.o.b.
On the other hand, sometimes you see a string of 4 or 5 "user ignored" markers all in a row and nobody has responded to them. It makes the thread much cleaner and easier to read.
Especially on politics the thread can go into yet another tangental tail spin, but I'm getting better at ignoring much of the response to the ignored after a quick scan. Quick scan because I can still learn from the responses, and sometimes open the IO's (ignored one's) post. Most of my IOs aren't on permanent ignore anyway, a few just longer term than others. My patience vacillates along with my sense of humor.
Using ignore still saves me time and keeps my blood pressure normal. I have only used it on a couple of people, but they are people who annoyed me with the vast wasteland that are their posts. I think I have gained at least 30 minutes of life back just by removing a certain "vegetarian-communist-chain smoker" living in Germany. My finger is still hovering over a couple of others.
You're not trying hard enough to get me really pissed. Tell me you voted for Bush and you think he's a God. Better yet, tell me you think H2Oman is a font of wisdom. If you say you slept with cjhsa and kissed his gun I promise I will ignore you forever. (bet you can't do any of it, so I can't hit the button )