I agree with Mark's comments about Dennison's offensive system and style.  I don't, however, see the Bills suddenly being able to outplay the Broncos just because Rick may want some revenge.

And why should he not have warm feelings for the Broncos?  He was a former CSU and Broncos player and was given a long leash given how poorly the Broncos offense played under his watch.  His coaching career didn't exactly set the NFL world on fire at the Texans and Ravens either.  He's the poster child for the Peter's Principle; rise to your highest level of incompetence, then stay there.  He'd probably still be the Broncos OC if Kubiak didn't retire from coaching.  Elway doesn't tend to meddle in a HC's decisions about staff.  He just doesn't renew the HC's contract a la John Fox.