A look at the incomplete 3rd down plays for context of the 2-9 efficiency:
Drive 1 - 3rd & 9 at TB 48 (PUNT)
(13:09 - 1st) (Shotgun) M.Jones pass incomplete short middle to N.Agholor (C.Davis). 0-1
Drive 2 - 3rd & 14 at NE 16 (PUNT)
(9:27 - 1st) (Shotgun) M.Jones pass short middle to B.Bolden to NE 23 for 7 yards (R.****rell, M.Edwards). 0-2
Drive 3 - 3rd & 10 at NE 42 (INT)
(3:39 - 1st) (Shotgun) M.Jones pass deep middle intended for N.Agholor INTERCEPTED by A.Winfield (R.****rell) [D.White] at TB 34. A.Winfield to TB 34 for no gain (N.Agholor). Pass deflected by NE 15-Agholor at TB 40. 0-3
Drive 4 - 3rd & 3 at NE 33
(13:22 - 2nd) (Shotgun) M.Jones pass short right to J.Meyers to NE 48 for 15 yards (R.****rell). 1-4
Drive 4 - 3rd & 5 at TB 47
(12:06 - 2nd) (Shotgun) M.Jones pass incomplete short right to N.Harry. PENALTY on TB-R.Sherman, Defensive Pass Interference, 10 yards, enforced at TB 47 - No Play. 1-5
Drive 4 - 3rd & 4 at TB 31 (TD)
(10:23 - 2nd) (Shotgun) M.Jones pass short right to B.Bolden pushed ob at TB 24 for 7 yards (M.Edwards). 2-5
Drive 5 - 3rd & 17 at NE 41 (PUNT)
(2:39 - 2nd) (Shotgun) J.Meyers pass short left to B.Bolden pushed ob at TB 44 for 15 yards (A.Winfield). Backwards pass from NE 10-Jones to NE 16-Meyers at NE 34. NE 16-Meyers backs up and completes a forward pass to NE 25-Bolden. 2-6
Drive 6 - Kneel down (END OF HALF)
Drive 7 - No 3rd downs (FUMBLE)
Drive 8 - 3rd & 12 at NE 21 (PUNT)
(8:25 - 3rd) (Shotgun) M.Jones sacked at NE 12 for -9 yards (J.Tryon). 2-7
Drive 9 - No 3rd downs (TD)
Drive 10 - 3rd & Goal at TB 9 (FG)
(5:21 - 4th) (Shotgun) M.Jones pass short right to B.Bolden to TB 9 for no gain (S.Barrett). 2-8
Drive 11 - 3rd & 3 at TB 37 (MISSED FG)
(1:03 - 4th) (Shotgun) M.Jones pass incomplete short middle to J.Meyers (L.David) 2-9
Summary of 3rd down plays:
Incomplete: 2
Incomplete (Penalty): 1
Complete (no gain): 1
Complete (fell short): 2
Complete (1st down): 2
Intercepted: 1
Sacked: 1
The 2 completed plays where they fell short were for 7+ yards so they could be counted towards the 3rd & 3 as positive plays. A penalty saved an incomplete. So you could say that Mac went 4-10, still not good. Seems that Bill didn't think Mac could make the play so he chose to kick it.