Because while pass-rushing is his strong suit, it isn't his only role. He drops in coverage and fills gaps against the run. The LEO's only responsibility is to get upfield (or in Branch's case, let the o-line get distracted).

 

Now, I could see Mack dropping down as a Designated Pass Rusher for passing downs, or being used in the Lightning Package we had so much success with this year. But just as a LEO? No, it'd be a waste.

 

It'd be the equivalent of just letting Deion Sanders play cornerback. Yeah, he'd be really good at it, but you're forfeiting his amazing return ability and his firepower on offense as well.

 

Edit: It's why (along with upper-body strength issues) Dion Jordan had trouble this year at Miami. They drafted a linebacker who was really good at coverage (could man up on slot receivers) and above average at pass-rushing, and put him in a spot where he'd have to stuff the run, which isn't his strength.

 

When you have versatile players, you have to change your scheme a little bit to harness all of their talents.

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