You also post regularly on FR. After having been on FR for so long, one starts to remember the 'screennames' of posters. Most of the more 'vicious' posters have screennames I have never seen before.
I now see many nics I don't remember at all and I have a fantastic memory. So that means that 1) there posts, few as thy might have been until lately, never posted ANYTHING at all memorable 2) are "sleeper nics".