The Seahawks say they aim to be the best scrambling offense in the NFL — so it figures that’s what they’re doing this week: Scrambling once again to fix their offense.

The trade for Duane Brown, an excellent if belated move to shore up left tackle, and the decision to ride one running back are steps that should have been taken long ago. These moves at this late date are emblematic of Pete Carroll’s offense: They never seem to have a good plan.

Even the best part of their offense, Russell Wilson, was mostly an accident. He was an undersized afterthought in the third round, drafted only because John Schneider pushed so hard for him. He was the surprise winner of a clumsy three-headed QB battle — and then the coaches handcuffed his talent for half his rookie season.

Wilson is one of the few things the Seahawks have done right on offense under this regime. He’s the reason Seattle’s often discombobulated and dysfunctional offense has ranked in the top 10 in scoring in all but one of Wilson’s seasons, the reason it put together the top two rushing seasons in team history, the reason it scored the second-most points in franchise history in 2015.

But, without Schneider’s brilliant find in Wilson, where would they be? Even Marshawn Lynch, one of Schneider’s other great offensive moves, couldn’t carry Seattle by himself (except perhaps on one great playoff run vs. New Orleans). It was the combination of Lynch and Wilson that gave the Seahawks a big rush, helping them win the Super Bowl. Of course, Darrell Bevell’s inability to call winning plays near the end zone cost them the second one.

Without DangeRuss, the Seahawks would be a middling team — because Carroll, Bevell and Tom Cable just don’t know how to establish a consistent offense.

They’re always scrambling.

Let’s look at the ways Carroll — a defensive coach, let us remind — has bumbled through trying to put together Seattle’s scoring side.

For starters, he has a bizarre coaching setup — with Cable in charge of the running game and Bevell overseeing the passing game and calling plays (with input from Carroll and Cable) on game day. It’s a three-headed monster that has trouble staying in sync, often smacking foreheads (like many fans when they see what these guys come up with).

Cable gets credit for cobbling together line pieces during the Super Bowl seasons, when key blockers (Russell Okung, Breno Giacomini, Max Unger) were hobbled for much of those seasons.

But he has failed to build any consistency in that unit. Brown is the fourth left tackle in two years, and Cable has used three centers since Unger was traded in 2015 (used four when Unger was injured in 2014). Right tackle has gone from Justin Britt (2014) to Garry Gilliam (2015-16) to Bradley Sowell (three games in 2016) to Germain Ifedi. And Cable has used four right guards the past two years.

As for Bevell, there are times when he finds the right rhythm of play calls and the offense clicks. But he has major problems in the red zone (some of them predicated on the poor line), he doesn’t know how to use a Pro Bowl tight end and the Seahawks can’t execute a running back screen play to save their lives (or their third downs). And don’t get us started on those ridiculous receiver bubble screens. It all adds up to very inconsistent performances that often rely on Wilson to bail out the offense.

Always scrambling.

Outside of trading for Lynch and drafting Wilson, many of the offensive personnel moves have been just as head-scratching as the coaching.

In 2010, when Carroll and Schneider arrived, one of the first things they did was overpay to acquire Charlie Whitehurst — an unproven third-string QB from San Diego. He bombed in Seattle and was gone back to San Diego after 2011.

Desperate for a quarterback in 2012, Carroll and Schneider flew to Denver and tried to recruit Peyton Manning from the tarmac. Their faux pas failed embarrassingly.

They ended up signing Matt Flynn (a good move at the time) and then surprisingly drafted Wilson in the third round — at the urging of Schneider. But Carroll then staged the dumb three-headed QB battle with Flynn, Wilson and Tarvaris Jackson, who wasn’t really an option.

Wilson beat out Flynn with some spectacular preseason play, but then the coaches put the clamps on him for the first half of the season — Carroll later lamenting that they didn’t turn him loose and let him run more earlier. Wilson was the X-factor who lifted the Seahawks into the playoffs in his rookie year — and has kept them there ever since, despite the dysfunction swirling around him.

Always scrambling.

Schneider has tried to add to the offense around him, but most of the moves have been busts because of injury, attitude or poor coaching — often leading to Schneider scrambling to make up for the failures.

Schneider has paid big for two good receiving tight ends — Zach Miller in 2011 and Jimmy Graham in 2015 — and neither has been used consistently well by Bevell. Good moves by Schneider wasted by poor play calling.

Schneider also has made major gambles for wide receivers — paying a ton to get Sidney Rice (in 2011) and Percy Harvin (2013) from Minnesota. But both were injured too much, and Harvin quickly became the same clubhouse cancer in Seattle that he had been in Minnesota. Seattle’s passing game ended up using undrafted Doug Baldwin and Jermaine Kearse during the Super Bowl seasons, when Seattle relied entirely on the magical Wilson and the monstrous Lynch to create offense.

Always scrambling.

Schneider also has tried to fortify the backfield. Robert Turbin (2012 fourth-rounder) was a nice backup to Lynch. Christine Michael, a second-round luxury pick in 2013, turned out to be a headcase who couldn’t beat out Turbin, and C.J. Prosise, a third-rounder in 2016, appears after 23 games to be an injury bust.

Undrafted Thomas Rawls was off to a fantastic start as Lynch’s replacement in 2015, but he has done nothing since a broken ankle ended that season. Chris Carson, this year’s rookie star, also was lost to injury — and it remains to be seen whether he will seize the job again when he returns next year.

Alex Collins (2016 fifth-rounder) is having great success behind a better Baltimore line after the Hawks released him this past summer. Collins was expendable because the Hawks had added Eddie Lacy, but they have been shuffling him in and out all season.

Now they finally realize what everyone else already knew: A running back needs to get into a rhythm. You can’t yo-yo him in and out of the lineup. So the coaches say they are going to let Lacy run this week. We’ll see how long they stick with it.

Always scrambling.

Seattle’s once strong running attack has fizzled since Rawls was injured in late 2015. It averaged 99.4 yards per game last year (ranking 25th) and has been even worse this year, averaging 97.6 (21st). Without Wilson’s 27.7, it would be about 70.

It has been so bad that Michael — brought back in 2016 — is still the leading rusher over the past 23 games, even though he played in only nine before being cut last November.

That leads us back to the biggest problem: the offensive line. It’s true there is a dearth of good college linemen these days and NFL practice rules limit the chances for improvement, but Schneider and Cable deserve blame. We previously explored all of the possible causes for their failure, from scheme to injuries to lack of a succession plan.

It’s not about paying guys. None of the linemen from the Super Bowl champs were worth paying because most of them couldn’t stay healthy or play consistently well. But the Hawks didn’t develop replacements. Rather than draft good linemen such as David DeCastro, Terron Armstead and Joel Bitonio, Seattle chose speed in Bruce Irvin, Michael and Paul Richardson.

Rather than stick a player at one spot to let him get good at it, Cable moves guys around in the name of flexibility and versatility. If the Hawks drafted talented players and left them where they succeeded in college, rather than “coach up” athletic projects, they wouldn’t have to figure out where guys should play and they might be able to develop some chemistry.

Their strategy is what led Britt to start at three positions in his first three years. It’s what led to the ridiculously bad Drew Nowak experiment in 2015. It’s partly what led to undrafted neophyte George Fant playing left tackle last year. And it’s what led them to draft “four players in one” Ethan Pocic in the second round — yet not find a starting spot for him until Luke Joeckel was injured.

After last year’s O-line debacle, Schneider admitted Seattle went too young on the line (he regretted letting veteran Jahri Evans go in final cuts). It’s why he tried hard to sign T.J. Lang this year and then gambled on Joeckel being healthy and added veteran Oday Aboushi.

But the offensive line once again has been full of neophytes — four of the five starters new to the team or their positions — and Rees Odhiambo has struggled mightily as the third left tackle since Okung left after 2015.

Schneider and Carroll knew they had to do something before a third straight season was derailed by the front five. So now they’ve got a new plan.

But, hey, that’s the Seahawks’ offense: Always scrambling.