I've never seen that.
though i think someone saying it was an addon that was used for actual raiding says a lot about why i havent seen it. i mean if your vent is that busy i suppose its useful to keep the flow of information clear, but not that hard to say "yuss i got item" or whatever in a less busy guild. certainly awkward to me lol
well if you're going to /ignore someone over linking loot you're probably doing them a favorthat's definitely a good way to collect ignores