Professional Football Researchers Association Forum
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I think Howley's career is different in that he was effective at such an advanced age...he was a pro bowler at 35, and still a very good starter at 36. Also, Howley flip-flopped between weak and strongside OLB and was an elite performer on both sides.
Gradishar was the best defensive player on the best defensive team in football at one time (1977 Broncos), which is something Brazile and Howley can't say. Gradishar also has the 1978 DPOY award.
Reading through some old Dr. Z columns in the SI vault, and FWIW he anecdotally said that Brazile was inconsistent and would take plays off, and Howley was the 2nd best coverage OLB behind Jack Ham.
Personally, I always liked Howley and thought he has been overlooked. Was he better than Dave Wilcox? No. Was he better than Dave Robinson? Probably not in terms of 'eliteness'. Was he better than Chris Hanburger? Perhaps. Howley isn't a slam-dunk HOFer, but I think he warrants enshrinement and am 'rooting' for him since there will come a point when none of the HOF voters will remember him. That said, here is how I would rank them:
1) Gradishar
2) Howley
3) Brazile
But I think all would be fine additions to Canton.