At least that's what I get from Caldwell's retentions:
Jeremiah Washburn, the Lions young offensive line coach, was one of the eight who was retained. It was announced on Friday.To keep it in the family, Jeremiah's dad, Jim Washburn has also been kept on. The former Philadelphia Eagles defensive line coach, joined the Lions last season as an assistant D-line coach. Other assistants who will stay include defensive line coach Kris Kocurek, tight ends coach Bobby Johnson, running backs coach Curtis Modkins, assistant offensive line coach Terry Heffernan and quality control/special teams Evan Rothstein.
Washburn Sr. is a Wide Nine specialist, and they're also keeping the DL coach.

Their new defensive coordinator said he intends to keep the 4-3 system, but blitz more. The new guy had better watch his back after how Washburn undermined Castillo here, and the DC for Detroit last year (Gunther Cunningham) was fired. The pattern of guys having Washburn on their staff isn't encouraging; I suspect JW's one of those guys who doesn't want the full responsibility of being a coordinator and just wants to stick with what he knows (wide nine DL), but also is insubordinate when he doesn't get what he wants and doesn't understand compromise. The Eagles did do some modifications of the Wide Nine in 2011 to try and alleviate its problems with run defense, mainly moving the DEs a little closer to the line, but I'm sure Washburn wasn't happy about that either, especially coming from Castillo.