I was wondering that myself, along with how he's apparently familiar with the other two's posting style and country of origin, etc.  And yeah, for someone motivated enough it's pretty damn easy to write in a different style to try to make it look like a different person.  Plus we know mdayonliner has a motive behind trying to conceal his true identity.  All of that in addition to the other evidence should convince anyone skeptical about what's going on here.

That's always been my impression as well, and I don't think he's driven just by money.  He's motivated by a need for respect and validation, which is paradoxically why he's so vocal about telling you it doesn't matter if you don't trust him.  Starting fresh with a new account gives him another shot at a clean record--except his little quirks in writing tend to give him away each time and won't let him achieve that.