He's arrived mid-way through a season into a completely different environment, at a club that didn't sign him to be an immediate starter - other side of the world, adjustment etc etc. Give the lad a chance! If 18 months from now he's still not making match day squads then fair enough, but for now just grasp the fact that these things do take a little time. Other than Ryan Nelsen, not too many Kiwis have instantly hit the ground running in top pro ranks (people forget how ropey Reid was in his first few months at West Ham until he found his feet).
Plymouth strike me as a well run outfit - no way their research and scouting efforts have come up that short that quickly. It took Chris Wood time to find his feet - Waine possibly in the same boat...
Or yeh, maybe he is total rubbish, not up to it and will crawl back to the A-League - reading some of this thread that seems to be inevitable/his only option...