I also agree with this. It's the state of mind of a deep player that he's lacking, and, though it might deceivingly look like something you can easily slip into, I'm not sure it's in Tomas' DNA to abandon the attacking instinct (yeah, yeah, snide remarks, sideways passing, etc.).
He is actually very flexible and has an impressive ability to change roles within a game between the mid roles and even the wing - all that thanks to experience and a very good understanding of the game. This would actually strengthen the case for him taking the anchor position permanently.
But as I said, I can't see him wear that Art 100% responsibility, no adventure state of mind. I also think that this is at the core of his inconsistencies - passing range, but not only (he's sometimes playing vertically, and sometimes - well, you know…). Anyway, it's not a pure football ability/talent limitation, as far as I can see.