But his season would end in August.
Everyone/everything is a bit to blame for this situation - the front office that drafted the players who might be more usable AAA (or even AA) depth - or actual fringe major leaguers - at this point in their careers, the current front office for not signing more arms (even though I don't really blame them for avoiding last year's incumbents specifically) and MLB in general since no team seems to have enough pitching, in MLB or AAA.
Look on the bright side: last year's 5th starter - the one who was an upgrade over Gibson and Falter at the time - makes $13 million and hasn't been any better than Falter or Covey this year.
Eventually Nelson and Sanchez will get their shot too I imagine. But it's hard to believe Plassmyer was considered as good a candidate as Falter going into spring training. Then again, turns out he was.