A reader of Post columnist Thomas Boswell’s weekly chat asked how Redskins Coach Jay Gruden can improve this up-and-down Washington offense. Boswell’s answer focused on the difference between Washington quarterback Alex Smith and his predecessor, Kirk Cousins.

Many are missing one of the main points about the Skins offense. Alex Smith avoids turnovers, including lost fumbles, as well as any quarterback in the NFL and far better than most, including Kirk Cousins.

The No. 1 factor in the NFL, far above anything else in statistical terms, is turnovers. It’s been that way since (at least) George Allen first made it a religion with the Rams and then Over The Hill Gang to get takeaways and avoid turnovers. That insight is now 50 years old. Now, everybody looks at interceptions, but they miss the fact that some quarterbacks lose a lot of fumbles while others barely ever lose one.

For example, in the last four seasons, starting with 2015, Kirk Cousins has had 55 turnovers in 54 games started. Of those, 16 are lost fumbles, including another strip-sack fumble for a touchdown return against the Cardinals on Sunday. That was Cousins’s fifth lost fumble this season, which leads the NFL.

Smith is remarkable. Since ’15, in 51 games as a starter, he only has 28 turnovers, including just six lost fumbles. SIX in 51 games.

So, Cousins has almost twice as many total turnovers as Smith since 2015: 55 to 28.

Smith has limits. But his single greatest strength is what does not happen: losing the ball.

The Skins won on Sunday against Carolina for just one main reason: a 3-0 edge in turnovers, which is huge. The best thing Smith did was what he didn’t do. As always, he protected the ball both in the air and when it was still in his hand. (One fumble on Sunday was recovered by Trent Williams.)

This “ball protection” is the main reason I now think the Skins are more likely to go 9-7 (or 8-8), rather than their 20-year norm of 7-9. They lack many things. But, since at least the early ’70′s when I first worked it out for every NFL game, the team with an edge in turnovers-takeaways, even by just +1, wins more than 80 percent of all NFL games. Nothing else correlates nearly as well. There is no other stat where “winning” the battle — yardage, penalties, time of possession, nothing — correlates more than the low 60s in percentage terms. Winning in turnovers is more than 80 percent.

There’s plenty Smith can’t do. He’s 18th in QB rating at a mundane 91.9. (Mundane by 2018 standards. Not mundane for ’78, ’88 or even ’98). Eli Manning, who can’t play dead, is at 90.9. Cousins is 10th in QB rating at 102.7.

But overall, I’d say that Smith is about what I expected, especially with the Skins' injured skill-position players and total lack of a No. 1 wide receiver. Okay, he might be a hair less than I expected, even more timid than advertised, and a game manager. But that could change as he gets more familiar with Gruden’s system.

I’ve seen five of Cousins’s six games with Minnesota, and I’d say he’s doing less with the Vikings than I expected. I’m pretty close to thinking that, while a very nice top-12 QB, he’s not quite as good as I thought he’d be once he got Adam Thielen and Stefon Diggs to help him. He’s really fumbled too much, and in bad spots on the field, with significant damages to the Vikes.

The difference in turnovers between Cousins and Smith is dramatic, and evens up their ability. I’d still take Cousins head-to-head, not even factoring in age. But not by much.

Cousins wanted out of D.C. for years. Nothing was going to keep him in D.C. In my opinion, the basic problem was his repulsion at the Skins' culture and the internal backstabbing, which would have turned on him at some point if he’d signed a long-term deal. He wanted to leave with his dignity, something few have done under Daniel Snyder. He engineered it and got out as clean as you can. The Skins did not so much mismanage negotiations as they created an atmosphere from which Cousins wanted to flee. In other words, it was their fault. Just not in the way it is usually presented, as front office or ownership bungling. It was bigger than that. It was “let me out!” As I said, that’s my opinion. But it’s firmly held.

What’s impressive is how well they salvaged a bad situation by trading for Smith. Late in the Saints game, I thought it looked like he’d quit, gotten demoralized, with awful body language. But he’s a pro’s pro, and he bounced right back on Sunday.

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