In only six seasons, what he did and accomplished here had historic impact and influence on the Patriots and the sport then and to this day. Ernie Adams and Bill Belichick, to name two, attest to this.
And he did it despite the Sullivans. Billy deserves credit for the hiring, as Chuck was 'controversial' over some recruiting violations at Oklahoma. But he and son Chuck not only did whatever they could to sabotage our Super Bowl chances, they drove Fairbanks out of town.
I cannot blame Chuck at all for leaving or how he did. If you need me to recount how the Sullivans undermined him (in even worse ways than Kraft did to Parcells), I can. Even with all that, in later years Fairbanks expressed regret about it.
He and his players are not responsible for Dreith and Tatum. They should be judged on their own merit and contribution.