Strange system you have in QF!!
Most other Airlines in the World allow the F/O to park the Aircraft IF the tiller is fitted AND the docking system can be used from the right seat, or a marshall is in place.
We've been allowing this for years in CX and not once has anything un-toward occured. I've found most F/O's quite able to park the beast.
With the Captain backing up on the brakes and watching the terribly complicated taxying manoeuvre it's a no brainer.
