The genetical difference between human beings and chimpanzees is only 1 % of total DNA. The other way: they are 99 % the same.
But what a huge difference in appearance, behavior and "culture"!
How minor is the genetical difference between you and me and f.e. Louis then?
Well, in contrast to race-horses, human beings and chimpanzees have not been artificially bred for a single purpose for some 30 generations by now. So, the genetical differences between race-horses may even been smaller than between human beings.
On the contrary: true science has proved that the differences in race-horses' performance is only by some 20 - 25 % caused by genetics. The more "environmental influences" you consider in those estimations the more the "influence of genetics" is diminishing (which is a problem of the methods used for those estimations, too).
But 95 % of tb-literature is on breeding and not raising and training and other perhaps important environmental influences on performance.
Anyway: what does "inbreeding to a sire-line" then really mean? We, the tb-breeders, do that for almost 200 years to Eclipse - 100 years before Phalaris, 50 years before Northern Dancer and his sons were born.
As Phalaris's line is florishing more than even even in his 8th - 10th generation of his progeny all the bad influence, which may have been in him (nobody did say till now which ones?!) has been washed out.
Why should "inbreeding" to Phalaris in 8 generations may be bad and "FFI" to that roarer (!) Pocahontas in 15 generations may be good to the breed?
After some 5 years and 430+ pages of this weird thread, we are still standing at the very beginning and haven't moved a single footstep.
All I can see is: Louis is caught and mumificating in his narrow walls of perception.
Sorry for that loss of weathy lifetime.
Let's hope the "young" breeders and those "new in the business", to whom Louis has dedicated his work, do see that nonsense.