It's a rare admission of structural and organizational concerns in both player readiness and in the coaching approach to defensive play design. Rather than making rapid adjustments, Tomlin is clinging to familiar tactics that are not working against contemporary NFL offenses. Couple that with the fact that the Steelers rank near the bottom of the league in missed tackles per game means that fundamentals aren't being coached and or made a point of emphasis. There are clear communication problems resulting in players out of position and overall confusion on who is doing what.
Also, Predictability and exploitable weaknesses with defense have opposing teams targeting the same play designs against the Steelers successfully.
Points allowed per game: 29th
Yards allowed per game: 29th
Passing yards per game: 26th
Average time of possession: 27th
If I'm Art Rooney I'm pulling the coaching staff into my office and asking them what the **** I'm paying for?