It's not that he's not talented...
It's that impressions aren't enough to support a comedy show. Caliendo is a strong impressionist, but he's just not that funny, which may be the fault of the writers and not so much Caliendo himself. The show doesn't work, everyone pretty much agrees. I don't blame Frank. The show proves that a good impressionist isn't all that entertaining. Funny in theory, but not in execution.
"Man is born crying. When he has cried enough, he dies." - Ran