its not like the deaf police are going to show up and bust you. the "rules" aren't rules so much as "taboo".
that was more of a "burn" than a sign name, if i read it right. the guy isn't going to go around and proudly display his new sign name, its more a name for you and your buddy to use to refer to him.
i do it all the time, i make up signs, i change deaf signnames when i wanna throw a dig thier way, and break prolly every other "rule" there is.
if it was a friend, and he really needed a sign name, that he would use. and when he met deaf in the future would use it, then it would mean more coming from a deafie.
