Go back and watch the Vanderbilt game and you will glaringly see what I'm referencing. It's not that our guys aren't good/great football players, some of them are just simply being asked to do some things that they weren't recruited to do. Side note: This is not an excuse for the lack of effort and execution from the last 6 quarters.
The 4-2-5 depends on pressure and athletic players all over the field to be successful. Particularly up front, some of our guys are more dispositioned to 2 gap or control their gap via lock, peak, shed techniques. Ideally, KW would like guys who can slash through gaps and create penetration and chaos in the backfield. The learning curve for the secondary and LB's is much less than the big guys but we have some unproven guys that are being asked to play at a high level and that is where we are seeing inconsistencies there, not necessarily that they are not suited for this defense. Sam linebacker is the position where we are going to need a "unicorn" who can cover man to man but is also big enough to handle OL and be a run fitter.