You don't have a monopoly on what words mean, lol. I played on multiple accounts simultaneously without behaving differently. I just didn't want ST'ers begging me to play ST when I was playing with the other kiddos. No doubt, however, that my other accounts would have been known as smurfs.
When he had tournies, people smurfed all the time. The simple fact that you were playing with people you normally didn't made smurfing quite easy.
You guys do let randoms in your games (see: Sidey). And I guess if you're just silent/vague, that is a "change in personality."
Grim could have been someone before, but he wasn't another concurrent player. Either way, this discussion has no relation to the topic. Even if he was Philo, he was still an east player and ranked higher than you. Being emo or a smurf doesn't really effect that.