The D made huge improvements last year from the beginning of the season to the last, I am hopeful we will see it again over the course of this year.
As far as the secondary, and losing people at corner... I have seen less dropoff than I expected (and I didn't expect as much as some to begin with). Bennett and Hunter were.... average. Current corners, slightly below average but way more upside. And it is showing up in the TO margin. IU has always given up big plays on blown coverages and missed tackles. Happened all the time last year. At least this year for most of those, this secondary has responded with a huge play of their own which was not the case before.. Bennett didn't give us anything Fant hasn't, thus far. He is still a bit undersized but his reactions are great. Cook is a better nickel this year than Fant was last year. Brown has made/missed as many plays as Hunter did.
Antonio Allen we miss, but how much? From my estimates, Crawford has the same # of career interceptions through 3 games as Allen had through 2 seasons. He is more rangy and athletic, and seems to grasp the basics of safety a lot better than Allen did. AA spent his HS days headhunting, not covering. And too often he tried to do the same at IU.
The talent pool keeps getting better and better.
Not saying we have a great D, but echoing OldCougar that the direction of the program, and even the secondary, is trending in the right direction.