Some of it depends on how DB's are taught. The eyes can get one in trouble - looking into the backfield while you are trying to cover a guy. Generally, it is about leverage and the off hand keeping contact down low. I would say the DB technique in the past was much better for the D we were playing. I doubt there is a DB coach who does not teach their players to turn and look for the ball when they read the WR making their move.
Go out on the internet and look up Quarters Defense and even some articles on the Michigan State D. It will give a whole different perspective. I will warn you that much it is pretty technical with their terms. To me it explains where we are weak which is to the outside.
Overall, the biggest problem I see is confidence and footwork. If you lack the confidence to be in the right place and your footwork doesn't get you in good physical position, there is no way you can look back for the ball. Your body is just not in position to make a play even if you see it coming.
I have been most disappointed with our DB play because of technique and footwork, they just seem off balance and out of position to often. Now the question is does that come from physical or mental mistakes? I don't know. Read some of those articles on Quarters D and you will see there are a ton of rules for players.