is it a kind of dream?

Good point. I'm listening to McGann read the movie novelisation (but I've not really reached the Master yet, not as more than a blob, anyway) so I'll see if book!movie!Master is better. He has to be, really. Even Chang Lee has a family history in this thing.

But even if Roberts was a rather crap (and slightly disturbing) Master, the characterisation was consistent with his backstory. He was getting a bit crazy back at Ainley, cos he spent a while rotting on Terserus, and then there was more rotting in a statue (and, personal fanon here, he might've had bits of Tremas in his head after that), then maybe the Cheetah thing added to the unbalanced, and at some point after Survival he was zapped by Daleks (although Rassilon knows why) and then got to slime around for a bit as a snake... I say he's justifiably crazy by the time he's Roberts :o) Wow, he really is fucked up...