I'd guess it has to do with the RPO. If linemen go more than one yard downfield on an RPO it's an ineligible man downfield penalty.
So to avoid that from happening our linemen stretch block horizontally instead of blast blocking vertically.
This is the root of the problem last year too, and the reality is that a pass calls for a different technique than a run, and in a RPO, they really can not be aggressive with either one of them, so they look bad at both.
But in the First half of the Vikes game they were firing off the ball and running run plays with what appeared to be some conviction and results, then Patterson got stuffed on a off tackle run and they proceeded to run sweeps and WR screens the rest of the night.
The RPO confuses our O-line and they are not talented enough to be second guessing what the play actually will be.
Perhaps this is why they are always looking behind them to see if the RB or QB was tackled so they know what option was taken