So using that point back to Hurts, he performs, against good teams and has the ability to manage a late comeback. These are the qualities you need in the play-offs as you're not usually playing a blow-out vrs the better teams in the lead.
As to the second part of your sentence, it's not only the 'poor play' its how the QB RESPONDS to the poor play. No comeback comes down to a 'perfect' drive(s), receiver drops, blown coverage, penalties.....it's how the QB responds, in adversity, can they put the poor play behind them or do they compound matters. That's where Hurts succeeds....and for me that's where I dont feel confident in Dak.