The Tampa Bay Buccaneers started Josh McCown last Sunday. Lovie Smith thought he provided a spark to the offense, and at first glance he did looks a little better than Mike Glennon: he produced 301 passing yards on 42 attempts, completing 63% of his passes and didn't throw any interceptions until the game was basically out of reach. Improvement!
The reasons for that improvement were fairly simple. The offensive line superficially seemed to play better, but that was mostly an illusion: McCown made their jobs easier by getting the ball out on time, to the right players. He didn't display his early-season tendency of hanging on to the ball, and at several points managed to navigate the pocket to create some room for himself or to take off and get some yards on the ground. That athleticism added a much-needed extra dimension to the offense.
McCown was also more accurate than Glennon, who has struggled on deep balls and who's general ball location has been sub-par. The veteran figured out that throwing the ball high is a better strategy than targeting a receiver's crotch when he's 6'5", and also seemed to have a better general idea of locating the ball where the receiver can get it, but the defensive back can't. Not that McCown was perfect in this area, but he was better than Glennon had been.
On the other hand, Josh McCown made some pretty terrible decisions. He eventually threw two interceptions, though we can probably excuse one of them on the basis of it being a desperation throw when the game was already out of reach anyway. But he had two more dropped interceptions, another couple of close calls and an incompletion that was dangerously close to a sack-fumble.
In other words: Josh McCown may have been generally more accurate than Glennon and he had better timing, but he was also really lucky not to have turned the ball over a disastrous amount of times.
Ultimately, the Bucs have two solid backup quarterbacks, neither of them good enough to carry an offense. And the offense itself isn't good enough for them to just be game managers. 2015 NFL Draft here we come!