| Personally, I don't use the ignore function, I just use my own discretion.
For example- I found myself charging into piracy threads like a Barb/Paladin (yeah, I know) intent upon textually swatting down those who misunderstood/mis-stated/ignored the laws regarding piracy because I'm an Entertainment lawyer.
Then I realized:
1) it was doing almost no good- most of those people weren't listening.
2) it was driving my already high blood pressure up. At times, I could actually hear the blood rushing in my veins...RAWR!
3) my posts on the subject were spiraling ever closer to being ban-worthy in their hostility...even when I tried to be cool, calm and collected.
So instead of putting certain posters on ignore, I instead just stopped participating in piracy threads. | 
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