Given that OSU was the most complete offensive team in the country, I am certainly not sure of my first factor ever being successful....but we needed to be able to play their receivers to a draw. I am far from certain anyone could do that when the stakes are high.
The second factor to me was not being able to move the ball consistently with passes of 7+ yards. The three and outs in the first half allowed them to gain confidence while tanking the ND defense in that regard.