By Joel H. Cohen Joel H. Cohen NEW YORK — “Dress British, Think Yiddish” is an unknown philosopher’s formula for success. I didn’t ask actor Steven Skybell his favorite clothing style, but I’m absolutely sure of his smashing success in the lead role of Tevye in the all-Yiddish Broadway production of Fiddler on the Roof. When first approached with the idea, most of us would respond: “Bist meshugah?”/“Are you insane?” But Skybell had already played Tevye twice, first at age 17 at music camp, and then at 22 at Yale, and wanted to play him again as an adult. Knowing that Joel Grey was directing th…