I did pretty well with 4-4 in DII. Good DB's could counter almost all passing attacks (especially against WB and NDB), even against SG. As I moved up to D1A and D1AA the level of WR seemed to improve vs the DB difference and had to add a pass D - (Nickel) to offset those pass offenses. It will work with some tinkering, but you have more problems as the offenses get better and even your best DB are at a disadvantage.