They've been making changes.

None have worked.

The biggest change needed is talent at CB, IDL, and OLB/Edge.

Caldwell is likely not getting the most out of what he has, but:

• they've got only two guys in the secondary that can cover right now and one of them is a free safety. 
  
• Darious Williams apparently thought coming home meant he could phone it in or he just can't play the slot - or both
  
• They were counting on Shaq Griffin to not suck, but he sucked
  
• Rookie OLB is still learning - will take time to learn technique to shed blocks
  
• 4th year OLB is in a massive slump 
  
• Rookie ILB got exposed after tape showed him biting on pre snap motion and getting beat on shallow crosses easily
  

All these things add up to a need for development and a need for talent acquisition. 
Most of the suggestions flying around about "move this guy here and that guy there" may do a little bit after the changes acclimate in a few weeks, but are unlikely to make any meaningful change in outcome this season. 

Help is not on the way. This defense will likely struggle the rest of the season.

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