I'll bow to Agar's superior knowledge - on one hand it's still a Wire reject, when we're trying to leapfrog them and I'm not sure how that works... then again, we lack a running half and that's what he brings. He does have some X-factor when he's in form.
We're likely to get injuries in the halves at some point so 3 decent ones (4 if McClelland stays) might make sense. He can also cover FB which could be useful if Myler goes down and Walker doesn't recover fully.
Not sure I'd want to swap Hurrell for Austin but there is a kind of logic to the move if it comes off.