Adam Gase was hired as the Dolphins head coach last year. His tenure with the team has been both successful and underwhelming, which is pretty hard to do. The Dolphins are 14-9 under Gase, tied with the Packers for the 8th-best record in the NFL. It feels hard to imagine, but Miami has a better record than Philadephia or Denver since 2016, and has as many wins as the Falcons.

On the other hand, Miami has a -77 points differential, which is the 7th-worst in the league. That’s a very stark difference: most teams have records that are proportional to their points differential, but not Miami. Tennessee (11th in record, 20th in points differential) and Houston (14th, 23rd) are the next two biggest outliers in that direction, with winning percentage ranks that are 9 slots better than their points differential ranks; Miami is at +17.5, by being tied for 8th in record and 26th in points differential. The Saints (t-19th; 8th), Jaguars (29th; 19th), and Chargers (t-27th; 18th) are the biggest underachievers by this method.

The graph below shows each team’s winning percentage (on the X-Axis) and points differential (on the Y-Axis) since 2016. Miami is a pretty large outlier:

There’s a pretty simple explanation for what’s happening here. When they win, the Dolphins don’t win by much. The team’s 14 wins under Gase have come by an average of just 6.2 points; that’s the 2nd-lowest average margin of victory in the NFL over that time period, ahead of only the Browns… who have one win by three points. When they lose, they tend to lose badly: the Dolphins average margin of defeat is 18.2 points, easily the worst in the league since the start of the 2016 season. Take a look:

Team Wins Avg Marg Rk Losses Avg Marg Rk Diff JAX 7 18.9 1 16 -8.8 11 10.0 ATL 14 12.6 7 8 -5.9 2 6.8 PHI 13 12.6 8 10 -7.5 4 5.1 NOR 11 12.1 10 11 -7.3 3 4.8 CIN 8 13.3 6 13 -8.5 8 4.8 LAC 8 9.8 20 15 -5.7 1 4.1 BAL 12 13.8 3 12 -10.2 15 3.7 BUF 11 11.8 13 11 -8.3 7 3.5 NWE 19 13.7 4 4 -10.3 16 3.5 DAL 16 11.9 12 6 -8.7 10 3.2 SEA 14 11.9 11 7 -9.3 12 2.6 KAN 17 10.1 18 6 -7.8 6 2.2 SFO 2 14.5 2 21 -12.5 25 2.0 MIN 13 11.5 15 10 -10.3 17 1.2 ARI 10 13.3 5 12 -12.4 24 0.9 DEN 12 11.4 16 10 -11.1 21 0.3 WAS 11 9.2 22.5 10 -9.4 13 -0.2 GNB 14 10.2 17 9 -10.7 18 -0.5 CAR 10 9.0 24 13 -10.1 14 -1.1 PIT 16 12.4 9 7 -13.7 28 -1.3 DET 12 6.5 29 10 -7.8 5 -1.3 TAM 11 9.2 22.5 11 -11.1 20 -1.9 NYG 12 6.4 30 11 -8.6 9 -2.2 LAR 9 11.7 14 14 -14.4 30 -2.7 CHI 6 9.3 21 17 -12.1 23 -2.7 OAK 15 7.7 28 8 -10.8 19 -3.0 HOU 12 8.9 25 10 -12.6 26.5 -3.7 TEN 13 8.8 26 10 -12.6 26.5 -3.8 IND 10 9.9 19 13 -14.1 29 -4.2 NYJ 8 7.9 27 15 -14.7 31 -6.9 CLE 1 3.0 32 22 -11.7 22 -8.7 MIA 14 6.2 31 9 -18.2 32 -12.0

Or, said differently: under Gase, the Dolphins are 2-7 in games decided by more than 7 points, and 12-2 in games decided by 7 or fewer points. The very first game of the Gase era was a 12-10 defeat to the Seahawks when Seattle converted on two 4th down plays in the final drive and scored the game-winning touchdown with 35 seconds left.

Since then, Miami is 10-0 in games decided by 6 or fewer points.