I confess, I didn’t know that Drew Carey’s Improv-a-Ganza was a television show. I never had a chance to even watch it. What I did know, however, was Whose Line is it Anyway?, the long-running hysterical show imported from the UK and beloved by improv fans like me. With so many fantastically funny people roaming our fair city during Sketchfest, sometimes choosing the shows you’ll attend can be hard. Not for me, at least not last night: I couldn’t wait to get myself to the Marines’ Memorial Theatre for the second weekend in a row for an Improv-a-Ganza with Drew Carey, Ryan Stiles, Greg Proops, Chip Esten and Jeff B. Davis.