The Boston Celtics' offense has been one of the top-rated atrocities of the young 2018-19 NBA season. Just wait until Kyrie Irving and Gordon Hayward come back, we said. That'll be more than enough to get this team to the Finals, we thought. The Eastern Conference is the Celtics, and then everybody else, it was written. None of these early takes have aged well. Watching this team sputter out on offense has me reminiscing about the short, but sweet Isaiah Thomas era of Celtics ball that set the stage for the team we see now. A certain tweet passed through my Twitter timeline that got me thinking - what did those teams have that this one doesn't? The Tweet in question:

Offensive Efficiency under Brad Stevens the last 6 years:
27th
18th
10th
8th
18th
24th

By all means, let's continue to celebrate the genius of his offensive sets.

— Ryan Schwan (@SchwanBSS) November 16, 2018

Wait, the Celtics had a top-10 offense in the Brad Stevens era? Twice? If that's the case, then the Celtics once ran one of the best offenses in the league with the following players playing the most minutes (via basketball-reference):

1. Avery Bradley - 33.4 MPG
2. Isaiah Thomas - 32.2 MPG
3. Jae Crowder - 31.4 MPG
4. Evan Turner - 28.0 MPG
5. Marcus Smart - 27.4 MPG

That's damn impressive. David Lee played 30 games for the Celtics that year, by the way. Real quick, let's see who played the most minutes when the Celtics were 24th in offensive efficiency:

1. Jeff Green - 34.2 MPG
2. Rajon Rondo - 33.3 MPG
3. Avery Bradley - 30.9 MPG
4. Jordan Crawford - 30.7 MPG
5. Jared Sullinger - 27.6 MPG

Need I say more? Jared Sullinger was out of the league after two more seasons. Jordan Crawford even sooner (although he came back briefly). In fairness, maybe I didn't need to pick apart such a misleading and obviously poorly researched tweet. Still, I think it's a good starting point to address everybody pointing their fingers at coach Stevens as a possible source of the Celtics' problems. His system, however you define it, is working as intended. Players are getting tons of open shots and simply missing them. Per nba.com, the Celtics generate the most "open" shots of any team, where "open" means that the closest defender it within four to six feet. They're shooting a dreadful percentage on those shots, so we need to dig deeper than shot quality to find the problem. I've got two observations as to what the problem might be.

Observation #1: Jaylen Brown's involvement in the offense (and who else gets to touch the ball)

Players with an expectation to score consistently need the ball in their hands to get into their groove. Per nba.com, Jaylen Brown touches the ball about 30 times per game, while no other Celtics starter averages less than 44 touches. There are a lot of problems that become evident when you see who gets the ball the most each game.

1. Kyrie Irving - 74.7 touches per game (TPG)
2. Al Horford - 54.5 TPG
3. Jayson Tatum - 45.3 TPG
4. Gordon Hayward - 44.9 TPG
5. Terry Rozier - 42.8 TPG
6. Marcus Morris - 40.4 TPG
7. Marcus Smart - 35.0 TPG
8. Jaylen Brown - 30.4 TPG

Now, here are the players from the list who score more points per touch than Brown: none of them. This is an odd realization, given that almost every other possible metric would show you that Brown has been the weakest link for the Celtics this season. It doesn't seem to make sense, but I think I have a possible explanation for it.

My super galaxy-brain theory

The offense isn't bad because of Jaylen Brown. It's bad because Brown doesn't get to participate enough. Bam. I went there. His usage rate of about 20 percent is actually higher than some of his teammates who get more touches, which could signal that he's not as excluded from the offense as I'm claiming. So, another theory to explain that: Brown's touches are often catch-and-shoot opportunities or otherwise short-lived chances to do anything with the ball. As someone who doesn't get the ball much, his opportunities become do-or-die scenarios where passing up a chance to score might lead to waiting a long time for the next opportunity. This could explain why so many of Brown's drives to the basket appear rushed. Even when he scores, it's by bouncing off one defender and arcing the ball just barely over the outstretched arm of another. Very few of his points seem to come easily, despite the fact that so many of his looks are categorized as "open".

Observation #2: Marcus Smart takes the bait (and other tales from deep)

Per Cleaning the Glass, about 55 percent of Smart's field goal attempts come from three-point range, placing him in the 76th percentile among players listed as a wing. I'm not sure why he's listed at that position, but it's a high rate regardless. No Celtic (except for Semi Ojeleye) shoots a higher percentage of their shots from three than Smart, which is just silly at this point. Real talk: Smart is my favorite basketball player of the last five years. Still, his three-point shooting is indefensible, and I'm writing this just after watching him knock down three out of four attempts against the Dallas Mavericks. Teams simply do not contest Smart behind the three-point line, or at least they won't compromise other defensive assignments to do so. They'll go under on screens before eventually raising an arm to create the illusion of deterring Smart from launching from two steps behind the line.

Meanwhile, the Celtics with the lowest percentage of shot attempts coming from three are Robert Williams (none attempted), Daniel Theis (18%), and Jayson Tatum (31%). Tatum, emerging from his sluggish start, is scoring on 40% of his attempts from deep on the season, which is especially impressive given how many late shot clock step-backs I've seen him take so far. He's unleashed a flurry of forced, off-balance shots, and yet his efficiency has only improved as the season progresses.

Here's the thing: Smart's shot selection isn't the problem. It's a signal of what I believe to be the greater issue, which is that many of the Celtics are overthinking what they do on offense. If the Celtics had a dollar for every Tatum pump-fake followed by a drive towards the middle that gets interrupted by his own unnecessary and unconvincing crossovers, they would have enough money to pay his next contract. Tatum's ability to create his own shot is invaluable, but his fancy moves aren't creating shots. They're just a sequence of things he does before deciding to shoot. While the team defense has been questionable at times, it's habits like these that I believe to be the key factors holding the Celtics back. Shooting at a league-average rate wouldn't solve all the problems, but it would at least impact the loss column enough that people would stop panicking.

Can it be fixed?

Yes! History would tell you that Brad Stevens always figures things out one way or another, and yet here we are again. Stevens is known to run some weird lineups early in the year and see how things play out before slowly tightening the screws as the season progresses. Let the team figure their roles out before you decide that they're bad at them, and give Gordon Hayward a chance to get his legs back before you ridicule his progress. A lot of things need to work themselves out, many of which can't be solved in 20 games.