The latest Broadway revival of “Grease” used TV to find its stars. So how’d they do? “There’s the numbing sense of performers of undeveloped talent conscientiously doing what they have been told to do and failing to claim their parts as their own. The message of this latest ‘Grease’ is that anyone, famous or not, can star in a Broadway musical, a natural enough conclusion in the era of YouTube and ‘American Idol,’ when the right to be a celebrity is perceived as constitutional.”