I think the "fourth quarter" Taylor is just the good side of the "we're losing" Taylor. When we get down, Taylor knows that he has to take control and make sh*t happen! He'll start taking bigger risks like throwing passes into tight coverage trying to make a play rather than throwing it away. Or trying to sell the zone read better. He'll either throw an interception or fumble the exchange or he'll throw an amazing pass or break a big run.
Take the CCG for example when we were down by 14 in the first. He ran back 20 yards just to take matters into his own hands and take it to the house. He could have easily been sacked at the 5 yard line.
I think he just gets in a mode that he knows that plays need to be made when we're down and he starts taking chances. Those chances are either going to result in plays and boost his and the team's confidence, and result in more big plays. Or a turnover which makes Taylor want to take bigger risks to score on every play. The bigger risk usually resulting in more and more turnovers.
Even bo has said that when Taylor was young he had an attitude like he wanted to score on every play. When he was a freshman we saw a lot of break out runs and he got thrown into heisman talks. He also had a lot of fumbles and bad decisions but as time has gone on we've started seeing more of his "fourth quarter" Taylor come out.
Hopefully he just comes out this season, goes balls to the wall, and just destroys everyone.