From time to time I like to share with y’all an episode of “Martini Shot,” Rob Long’s behind-the-scenes glimpse at Hollywood life. (It airs weekly on KCRW, but you can subscribe to the podcast here.) Long, who landed a writing gig on Cheers when he was just 23, has a unique perspective on the “frivolous business” that pays his mortgage. This week, he takes a look at market research. You won’t want to miss it.