Some people somehow rewrite history in their own head, or can't realise what their effect on other people is, or something. I've probably recounted in my own lj the Case of the Person Who Caused Ongoing Enormous Ruckuses on the Listserv I Was Running (including saying on and off-list some fairly nasty things to myself), and then, when applying for jobs, asked me if I would be a referee (this was perhaps a bit sad, we had never met in rl, and person presumably didn't have many people to ask: but one could quite see why that was the case)