What is Northwestern's Clayton Thorson working on in spring practice?

Northwestern had an up-and-down season in 2016, losing its first two games to Western Michigan and Illinois State but rebounding to make -- and win -- a bowl game.

The Wildcats dropped off the national radar in some respects after that tough start, which obscured a really big development. That is, the actual development of quarterback Clayton Thorson.

As a redshirt freshman starter, Thorson helped lead the team to 10 wins, but he wasn't asked to do much more than manage the game. As a sophomore, Thorson showed vast improvement in virtually all areas. He more than doubled his passing yards, to 3,182, while throwing 22 touchdowns and just nine interceptions. In Big Ten games, he completed 60.9…