Sam Monson of PFF recently documented just how strong the swing to the pass game — and away from base defenses — is in the NFL:

Wow, in 2018 the league average for base personnel on defense fell all the way to 25%.



The Cardinals spent less than 10% of their snaps on D in base personnel.



If you're drafting any 2-down player anywhere on the first couple of days, you're doing things wrong. — Sam Monson (@PFF_Sam) May 17, 2019

This take is not wrong, but it shows the wisdom of Kyle Shanahan’s scheme — which goes in the opposite direction. He is zigging while everyone else zags, a high-risk, high-reward strategy.

Shanahan is building a run-first offense based on the outside zone run and play-action passes. He can force defenses into their base package, which they’re stupid to build up because everyone else is going the other direction. And division rival Arizona is precisely one of the teams not equipped to handle a strong run game.

The Niners now have three outstanding backs (Tevin Coleman, Jalen Hurd, and Jerick McKinnon) who can run or receive on any given play. If any of them lines up with FB Kyle Juszczyk in the backfield, how can a team move out of its base defense? But if they stay in their neglected base, Juice can fall back into pass protection, and the team can run four verts on play-action if they want to.

If a team plays nickel defense anyway, the Niners will be able to punish them with an explosive running game behind the strong blocking of Juszczyk and TE George Kittle — or flatten the quicker, smaller, lighter linebackers and defensive backs with Deebo Samuel slants, Kittle catch-and-runs, and Jalen Hurd just all over the place.

A counter-punching strategy like this has an advantage for roster-building, too. Offensive linemen who are better at run-blocking than pass protection are relatively cheap. Football Outsiders ranked the Niners line as 10th best in the NFL for run-blocking last year, but only 22nd for pass protection.

Even at the lowest point of last season, when Beathard was finally benched in favor of Nick Mullens, PFF ranked the team fourth in the NFL in running yards before contact, at 2.05. (Don’t forget that #1 running back Jerick McKinnon was out for the season.)

The danger of this strategy

So, why doesn’t everybody zag like Shanahan?

Because these trends are happening for good reasons, the league goes in one direction because it has advantages, and contrarians give those up, voluntarily.

In this case, passing plays are just more productive than runs. Running backs don’t last that long (Todd Gurley might be worn out already). And with any fullback less skilled at pass-catching than Juszczyk — meaning, all other fullbacks in history — you waste a precious roster spot on a guy who might not even show up in the box score.

Furthermore, if your run-blocking OL can’t protect your quarterback, you risk him getting injured. We saw what that looked like last year, and it was ugly.

Counter-punching is a risky strategy, and it depends on your timing and uniqueness. It’s kind of like selling the stock market short - timing is everything, and you can get killed if you have it wrong.

If the current trend is overdone and about to swing back, you’re a genius, and other coaches will start copying you. But if not, you’re fighting the tide, like a kid at the beach frantically reinforcing the walls of their sandcastle as the waves wash it away.

There’s also a real danger of letting nostalgia cloud your judgment, especially for Shanahan — the son of a coach who was very successful in the old style.

Personnel Problems?

This unique scheme depends on players who are skilled in both the run and pass game — hence the pass-catching RBs, Jalen Hurd, and Juszczyk. But when injury strikes, can you replace them?

The run-first OL requires a QB who gets the ball out quickly; hence, the improvement last year with Nick Mullens over C. J. Beathard.

Also, the college pipeline adapts to the jobs available. How many good FB prospects are there any more? I guess that the Niners picked up TE Levine Toilolo in part as Juszczyk’s backup — a great run blocker with just enough receiving skill to force defenses to account for him.

Problems for the defense?

There is one more problem with a contrarian offense. Your defense gets its practice reps against your offense, so if you have a unique offense, they won’t be as prepared for the teams they play against.

Hopefully, in this case, the offense can just outscore the other team, and this will overwhelm any harm to the defense. Besides, if the strategy works and other teams start copying Shanahan, the defense will be ready to stuff their fledgling attempts.