I play on custom sliders, and can't seem to either slow down the CPU D-line ACC or increase my own to match their speed.
I've given up manually controlling my DE's, as it actually makes them slower. (Seriously, try it yourself, you will be forced to wait when the ball is snapped to move your defender.)
But I always have issues with the CPU having DT/DE's that get to the RB mid handoff or beat him to the edge on stretches and toss/pitch plays.
I think the main problems are things that I can't even fix. If I knew how, I'd volunteer at EA and help program Madden 12, but I don't know anything about programming.
(Although if you ever want another tester I can drive down on the weekends...
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