That doesn't mean there isn't still room for improvement.
''His greatest achievement so far is his ability to progress and get better, really, and study and want to get better and learn and study each opponent on a daily basis, on a weekly basis,'' Gruden said after practice Wednesday, ''and understand that there is going to be change involved and adapt to that change.''
Publicly, anyway, the Redskins have not made clear whether they envision Cousins as their quarterback of the future. He can become a free agent after this season, his fourth since being drafted in the fourth round out of Michigan State.
Despite a 6-7 record, Washington is tied atop the lowly NFC East heading into Sunday's game against the visiting Buffalo Bills (6-7), and Cousins has started every game since Gruden's decision to elevate him above Robert Griffin III late in the preseason.
''When the season is over, then I look back and say `What did I do well? What do I need to improve upon?' I think the big picture, it's the team's job to evaluate, the coaches' job, (the media's) job. For me, I just focus on the next game, the Bills, trying to finish what we started and finish strong,'' Cousins said.
''There will be plenty of talk in the coming months about how I did over the whole span. But I feel like I'm still in the middle of it,'' he added.
''People remember how you finish, so regardless of what I've done the first 13 games, they're going to remember the last three. So there's still a lot of work to be done.''
Cousins' completion rate of 69.2 percent leads the league among players with at least 40 pass attempts this season. His 3,306 yards passing rank 11th, ahead of folks such as Aaron Rodgers, Russell Wilson, Andy Dalton and Cam Newton.
His 93.2 passer rating is more middle of the pack (15th), as are his 18 touchdown passes (16th).
And turnovers are still an issue, though not as much as earlier in his career. Cousins has been intercepted 11 times this season; only six QBs have been picked off more, and three of them missed time with injuries.
''We're still in the evaluation process,'' Gruden said, ''but I'm tickled to death to see how much he's progressed.''
A couple of the good signs:
- Cousins has five 300-yard passing games, tying a franchise record last reached by Mark Rypien in 1989.
- He's the first Redskins QB to open a season with a TD pass in 13 consecutive appearances since Sonny Jurgensen in 1967 (and the only other NFL players to do so this season are Wilson, Tom Brady and Blake Bortles).
''He's still learning, man. He's still fighting through some things. We're still coaching the heck out of him,'' Gruden said. ''But I like where he's going. I like what he's about - what he represents as a football player and as a person. We'll go from there.''
Notes: WR DeSean Jackson sat out practice Wednesday because of a bruised kneecap, but Gruden said he is ''confident'' the receiver will be available for Sunday's game. ... LT Trent Williams was among players limited in practice; Gruden listed his ailment as a foot. Asked which one, Gruden replied with a smile: ''You don't get which foot. All you get is `foot.' I don't know. I'm not even going to guess. He just said his foot hurt.'' ... TE Ray Hamilton was signed to the practice squad.
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