I don't think any QB would have elevated the 2015 Miami Dolphins to a 10-6 record. That team was an absolute disaster with key injuries across the board on top of organizational dysfunction, coaching incompetence, and an outright mutiny of the players.
Miami had the least amount of rushing attempts in the league. Tannehill had 586 attempts and the team rushed only 344 times. Let's look at Miami's 10 losses to see the discrepancy:
Week 2: 23-20 loss to Jaguars - RT was 30 for 44 for 359 yards and 2 TDs 0 INTs. Miller ran 10 times for 14 yards. Miami as a whole ran 16 times for 42 yards. Game was tied at 20 in the 4th quarter.
Week 3: 41-14 loss to Bills - What a bull**** game this was seeing as how I flew down to Miami for it. RT was 26 for 49 for 297 yds with 2 TDs and 3 INTs. Miller ran 7 times for 38 yards. Miami as a whole ran 20 times for 92 yards. Miami was down 27-0 at halftime.
Week 4: 27-14 loss to Jets - RT was 19 for 44 for 198 and 2 TDs 2 INTS. Miller had 7 carries for 26 yards. Miami as a whole had 11 carries for 59 yards. Miami was down 20-7 at halftime.
This is when Philbin was fired. In those 3 losses prior to him being canned, Miami threw the ball 137 times and rushed 47 times. How the hell is this supposed to be considered good coaching?
So Dan Campbell comes in and Miami wins their next 2 to get to 3-3.
Week 6: 38-10 win over Titans - RT was 22 for 29 for 266 yds 2 TDS 2 INTs. Miller had 19 carries for 113 yards. Miami as a whole ran 32 times for 181 yards.
Week 7: 44-26 win over Texans - RT was 18 for 19 for 282 yards 4 TDs 0 INTs. Miller had 14 carries for 175 yards. Miami as a whole ran 35 times for 248 yards.
In those 2 Miami wins, Tannehill had 48 attempts and had 548 yards. The team ran 67 times for 429 yards. This is called balance (could even be considered run-heavy).
Miami then faced NE on a Thursday night game. They lose 36-7 in a game where RT had 44 pass attempts and Miami only ran 13 times. They were down 19-0 at halftime. We gave Campbell and company a mulligan b/c it's at NE on a short week.
Miami is at Buffalo next. Keep in mind Tyrod Taylor had an average QBR of 140 in the 2 games he played Miami. RT had 35 attempts in a game where he was 26 for 35 for 307 yards (0 TDs/0 INTs and only 2 sacks). Miami as a whole ran 23 times so the balance wasn't as awful as usual. It's just that Buffalo ran 35 times for 266 yards (McCoy and Williams had 112/110 yds respectively) for 3 TDs. This was also the game where Watkins made Grimes his bitch by catching 8 balls for 168 yards. He also targeted 8 times. Miami trailed 19-7 at the half.
Miami stood 3-5 at the midway point of the season. Their next game was at Philadelphia. RT was 21 for 36 for 217 yds 2 TDs and 0 INTs. Miami as a whole ran 26 times. Philly on the other hand had 392 yards passing (Bradford/Sanchez) and overall had 475 of offense. How they lost this game I don't know.
Miami at home facing Dallas. RT goes 13 for 24 for 188 yds 2 TDs 1 INT. Miami as a whole rushes 14 times for 70 yards. 38 total plays in the game vs. Dallas' 66. Game was tied entering the 4th qtr.
Miami at the Jets. RT was 33 for 58 for 351 yds 3 TDs 1 INT. Miami as a whole ran the ball 9 times. Yes, 58 passes to 9 runs. A clear recipe for success. Marshall made Grimes his bitch with 9 catches for 131 yds and 2 TDs. 14-0 Jets at the half.
Miami faced Baltimore who was without Flacco and others. RT had only 19 attempts and 86 yards of offense while Miami ran 26 times. They won this game only due to Flacco being out.
Miami had the Giants at home on MNF. RT was 25 for 41 for 236 yds 1 TD 0 INT. Miami as a whole ran 22 times for 128 yards. The game was tied early in the 4th. Beckham ate Grimes' lunch with 7 catches 166 yds and 2 TDs.
Miami is at SD. RT was 20 for 24 for 216 yds 0 TDs 0 INT. Miami as a whole rushed 19 times for 44 yards. Danny Woodhead had 4 TDs for crissakes.
Last Miami loss of the year is home vs. Indy. RT was 26 for 38 for 329 yds 0 TD and 1 INT (sacked 6 times). Miami as a whole rushed 25 times for 82 yards. This was the game where Miami was at the Indy 5 on the last play of the game and 4 of the offensive lineman didn't block once the ball was snapped.
Lastly we get to the win vs. NE, who was playing for home-field advantage in the playoffs. RT was 25 for 38 for 350 yds and 2 TDs and Miami rushed 34 times (yay balance!). Brady had his worst game of the year in a game NE needed.
Bottom line: look at how many times Miami threw more than they ran. With the OL being suspect you'd think the coaching staff, even with the regime change, would've had common sense to change things up. Especially when Miami was 3-3 and 2-0 in Campbell's first 2 games.