Good Eats was on for 14 years and has 252 episodes, what more can you possibly ask for? That's a good run for any show nevermind one as labor and time intensive as Good Eats.
What makes you think his Good Eats host character is his "normal persona"? He doesn't play a caricature, just a character.
What makes you think his Good Eats host character is his "normal persona"? He doesn't play a caricature, just a character.