#1 Both were genuinely hated heel authority figures during their heyday
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The one thing that stands in favor of both Bischoff and Heyman is the fact that both have proven themselves as legit TV characters time and again in the past. Bischoff turned from an announcer to a major villain as a part of NWO during the Attitude Era. He reprised his heel authority role in WWE and feuded with the likes of Stone Cold and John Cena.
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Heyman did the exact same thing over on the blue show and did his bit towards putting over a white-hot John Cena in 2004, which led to him capturing the US Title from Booker T, and then the WWE Title from JBL. WWE has put these two in authoritative roles again, this time in a backstage capacity. A point can be made that Heyman and Bischoff are the two greatest heel authority figures in WWE history, of course after Mr. McMahon. It would be a disservice to the fans to not use these two amazing heels on WWE television.