The PFF play-by-play grading system does a great job of isolating each player’s role in production, and when it comes to quarterback play, we believe it isolates their contribution on each play as well as any metric.
While the overall grade is both descriptive and predictive, the beauty of the PFF system is using the entire database to pair the grade with the best pieces of data to better predict future performance. Based on the excellent work done by PFF’s R&D team in the QB Annual, we are better able to isolate the parts of a quarterback’s performance that are most stable from year to year and that are difficult to sustain.