The FB should be picking up the DT on these inside runs but constantly just runs by him going after a LB instead. The read is way off even with FB with great blocking skills

Hmm dunno about that, that sounds like a huge mismatch, surely the C or G should be picking up the DT, the FB should be attempting to get to the next level, which would be LBs.

Do you have an example?

What is actually happening is that at the start of the play each blocker is assigned who they are going to block. The DT -should- be getting picked up by a lineman while the FB would only pick up a DL if there is no OL to take him, otherwise he's going after the LBs.

I just used the DT as an example of the first one who gets in the backfield, it could be a DE, LB or whomever, either way the FB just runs right by whoever has penetration.

I would like to see an example of the FB or HB (on FB runs) ever picking up these players.

Having a good FB is great if you have a HB and/or that can block for you because he will get to the lb and turn a 3 yrd gain into a big gain.

I guess my best example could be any game that you run on 3rd and short. There is penetration 75% of the time and its usually all up to the HB to break that first tackle or its a 2 yd loss. Watch any game

Might be a case of the OL whiffing on their block but the FB is already targeting another player. That might be something to adjust. I'd like to see some examples if you come across any in the near future so I can see who the DL should have been blocked by and why the FB didn't block them.

You can pretty much see this in every game on 3rd and short runs dave.