At the end of 2014, four of the top 10 sires on the TDN North American General Sire List for last year were the four sires with first foals 2006 that have been so prominent since they first had runners in 2008: Gainesway's Tapit; WinStar's Speightstown; Darley's Medaglia d'Oro; and Lane's End's Candy Ride. Among them, by the end of last year, with seven crops of racing age each, they had sired 219 black-type winners (BTW), of which 104 were graded/group winners (GSW), and 43 were Grade I/Group 1 winners...