There is a user registered on Retrobike forum called lm1065, if you would go on to his posts,
you would see that stuff he says about HIMSELF is mostly something like: '' I agree pete matthews has a great reputation''
I was a bit shocked actually, how a grown man could act like this.
How daft you have to be ? (facepalm)
Also i was told by senior riders that he states himself as best wheel builder in the WORLD(yeah sure) and bunch of other jokes about him.
I believe this is not a case of split personality but pure narcissism.
Chances are it's his son posting - pretty sure he looks after his twitter account / web site etc, but yup, it doesn't look good either way...
He does lace together a decent wheel and like you, I hear he isn't too modest about it :) That said, I also hear he's a font of knowledge and always up for a conversation.