Actually he's been very good in coverage for a DE. I don't know that it's going to translate to the OLB position, but at least we've seen some indications that he's got the capability. As for your other comment, he's been absolutely tremendous against the run for the last several years.
I'm not entirely convinced that he can make this transition successfully. But for the last few seasons his greatest strengths have been his versatility, his intelligence and his ability to do a multitude of things well. It's not a guarantee of success, but it certainly bodes well for him and the Bills.