As an art critic in the theater reviewer’s seat, I found myself wondering why the art market continues to hold dramatic appeal, and why so few people get it right. Of course biographical plays have always appealed, whether done straight, like the play “Red,” about Rothko, or more dreamily, like the Seurat-refracting “Sunday in the Park With George.” Yet the big-money domains of the auction houses and the largest galleries remain stubbornly beyond most writers’ faculties.