Regarding Pompey\'s title

[SOCL]

Plutarch explicitly states that Sulla greeted Pompey as Magnus and ordered that the Senate ratify the title. The way Plutarch makes it sound, I do not believe it was quite as sarcastic as popular opinion states. In truth, I seem to believe this was more a political move by Sulla in order to keep power and yet still appease Pompey, who had a sizable force likely capable of causing much damage to Sulla.

I have also heard the theory that he bestowed upon himself said title, but what documentary evidence is there to support this? :?

Here is a previous discussion on this very same topic:
http://www.romanarmy.com/rat/viewtopic.php?t=14290