I would assume (hope) Rod had input as well.
Defense wasn't ancient when Garrett took over in 2010.
D-Line: Stephen Bowen was 26, Hatcher was 28, Olshansky(meh) was 28, Ratliff was 29, Spears was 27, Brent 22.
Linebackers: Spencer was 26, Ware was 28, James was 29, Lee was 24, and Brookings was 35.
Secondary: Mike Jenkins was 25, Scandrick was 23, Sensabaugh was 27, Newman was 32, Church was 22
Defense gave up under Phillips, but they weren't ancient minus a couple of players.
Ware was in his prime. 15.5 Sacks in 2010, 19.5 in 2011.