You'd think the nine-furlong GII Remsen S. might be a good measuring stick for GI Kentucky Derby potential because it's the only top-level, 1 1/8-miles American dirt race for juveniles before they turn three. But only three horses in the last 61 years-Thunder Gulch, Go For Gin and Pleasant Colony-have parlayed wins in the Remsen into a blanket of roses at Churchill Downs. Instead, in recent runnings, the Remsen has evolved into a pipeline for progress deeper into the 3-year-old season. Remsen winners have captured two of the last three...