A short look at the facts can place the situation in perspective. The “maternal damsire effect” relies heavily on the myth that a number of stallions, including Princequillo, failed as stallions but were highly successful sires of broodmares. The theory explains this so-called phenomenon by postulating that certain genes skip a generation within the pedigree of a stallion in his capacity as a sire of broodmares, while lying dormant within the pedigree of the same ancestor in his capacity as a stallion. The main problem with this theory is that those propounding it appear not to have questioned the old-wives’ tale that some stallions are more effective as stallions than as sires of broodmares.
In almost all cases this is a complete myth. Princequillo represents perhaps the best example of all of this fallacy. He was in fact a highly successful stallion producing 13% black type winners to foals of racing age (as compared with a current figure of 12% for the highly promoted Storm Cat). Amongst others he sired Round Table, arguably one of the fastest racehorses ever, and amongst his other claims to fame as a stallion we can include Hill Prince, Dedicate, Misty Morn, Quill, Rose Bower and Prince John.