I don't want to mention his previous username for some reasons I think should be left unsaid
Yet you mentioned it in the other thread vs sending a pm if you really wanted to leave it unsaid.
I personally wouldn't grant name changes to anyone as they could just lock the account and start all over, but noone wants to lose their rank. You should consider everything when choosing a name for a forum and be stuck with your choice or start all over under a new name. Just my 2 cents.