PFF - have y'all seen this

More wins
More TDs
Less INTs

Definitely inconclusive.
*today was the day that I had to let @TribuneUK know that wins are a team stat*
You do know wins are a team stat, right? But you are absolute right from a stat perspective; Carr had 6 more TDs in 6 more games and Jameis threw more interceptions. Outside of that, they were dang near equal in everything else with metrics leaning towards Jameis. Anyone that can read stats would tell you that they were pretty much virtually identical in individual stats. (other than the little detail of the Bucs having a higher point per game average than the Raiders while their defense gave up more points over those 4 seasons). This is the thing; when people bring up Derek Carr stats, they only talk about the Gruden years. When people talk about Jameis, they talk about his single season with Arians. You understand how that works now?