In a post three days ago, I went into some basic discussion about variations from the norm and how this is having an impact on breeding Thoroughbreds.

In that post, I described how biomechanics can help us to understand the changing norms within the breed. In terms of human society, this could be described as a conflict or struggle. But in the practical terms of the racetrack, it is all about winning races, especially the most important races.

As a result, the horses who win the most prestigious races become the most valued, even if they do not possess the traits for racing that can be reproduced most consistently.

As a result of this tension between consistent high ability and specialized excellence, there is a struggle for dominance between different types of racehorses. Pressures in breeding and racing, particularly from the commercial market over the past two decades, are moving to replace the typey, muscular, medium-sized horse typical of Type I and to replace it with the larger, rangier, power-centered horse of the P type.

Unbridled’s Song is a splendid type of a power horse, and he is very popular with the commercial breeders and buyers. On the other hand, Distorted Humor is the heir to Danzig, Mr. Prospector, and others of the Type I center.

Anyone inspecting these two stallions will be taken with their excellence. They are fine representatives of their differing types and have become immensely successful sires.

As an individual, Unbridled’s Song is hard to miss. He’s that big. Not only is the gray son of Kentucky Derby winner Unbridled tall, but Unbridled’s Song is very lengthy. He is deep through the shoulder, long in the hip, and set well off the ground. He is quite an imposing animal.

In contrast, Distorted Humor is a chunk. A horse with great balance, the chestnut son of Forty Niner has a robust body of average height, combined with good length through the body and good power from a strong gaskin and hindquarter.

Both of these stallions have sired outstanding racehorses.

With 10 crops of racing age at present (that’s 1,068 foals), Unbridled’s Song has sired 774 starters (72 percent), with 520 winners (49 percent), and 82 stakes winners (8 percent).

The best winners by Unbridled’s Song include champion juvenile Midshipman (Breeders’ Cup Juvenile), Breeders’ Cup Distaff winner Unbridled Elaine, as well as the additional Grade 1 winners Zensational, Thorn Song, Splendid Blended, Buddha, Songandaprayer, Magnificent Song, and Marylebone. And about 40 percent of his stakes winners are group or graded stakes winners, which is an amazing statistic.

These percentages from the progeny of Unbridled’s Song show that when he connects, he tends to put the ball over the fence, but there is simply no debate that the equally high-class sire Distorted Humor is more consistent.

From eight crops of racing age (812 foals), Distorted Humor has sired 634 starters (78 percent), with 484 (60 percent) and 79 stakes winners (10 percent). The best racers by Distorted Humor include Kentucky Derby and Preakness winner Funny Cide, as well as Grade 1 winners Commentator, Hystericalady, Flower Alley, and Any Given Saturday.

The percentage differences between these two horses are fairly small because both are really good stallions, but consistency is one of the benefits of the better-balanced Type I stallion such as Distorted Humor.

Even without the same level of consistency, the big power horse, like Unbridled’s Song, is popular for two reasons. These stallions tend to sire big, impressive yearlings that sell well, and when one of their offspring has all the components and makes it as a racehorse, the big power horses tend to be really good animals.

In the end, the goals and temperament of the breeder have a role here. If a breeder is more of a gambler who likes to swing for the fences, then the power horse with great size represents an irresistible item. If a breeder wants greater consistency and predictability, then the really well-balanced horse is the best bet.