Wouldn't that be hilarious if when they were thinking something they actually said it in thoughtspeak?
Rachel: <Shut up Marco!>
Marco: <I'll show you you tramp!>
Rachel: <What did you just call me!?>
Marco: <Oh, oops, did I think that out loud?>
Or if when Tobias was in his human form, say he was checking a girl out.
Tobias: <Man, look at that rack! *whistles*>
Girl: "Excuse me!?"
There could be a lot of funny errors.