I’ve been on movie sets and I’ve been on network TV, but in all these years I’d never watched a porn film being made. So last week while I was in L.A., I finally accepted an invitation. After lunch I drove out to the San Fernando Valley, parked in a neighborhood of modest homes and small warehouses, and walked into the studio of Brash Films. I spent about two hours there, watching and occasionally chatting. Everyone involved made me feel welcome. The most interesting thing I have to say about it all is—nothing. But maybe not for the reasons you…