Lest ye forget, another DA bungle: losing Aaron Glenn, Ryan Nielsen, and Kris Richard

This was discussed when it all went down. Neilson wanted our DEs to bulk up, which potentially was causing some of their injuries. Richard had a difference of opinion for DB play. If the offense was doing it's job, the defense would be a lot better right now like it was earlier in the season. Also, look at Richard's history, he starts out hot then fizzles out. Dude ain't even coaching right now.
That's the first time i'm hearing about that. Unfortunately those same DEs continued to get injured.

It wasn't lateral. Nielsen was given DC play calling duties. Some thing he would not get here, because DA calls the defensive plays. That's why he left.
This makes sense.