Interesting use of horses for inbreeding genetics.
The scientific consensus is that inbreeding (in both humans and right down to simple creatures such as mayflies, which has had extensive studies), while normally not bad first or even second generation, eventually leads to retardation of certain gene pairs, causing abnormalities, infertility via broken down or unusable sperm cells in males and a weakened immune system. I sincerely hope no human feels the need to keep to the same gene pool in the hopes of having the same qualities as a father-daughter horse breeding schedule.
You are talking about long term in breeding, where its absolutely true. However if used correctly (one or two generations) it's an excellent tool for solidifying and stabilising the excellent traits you want the offspring to inherit. By in breeding I refer to the pairing of the closest relatives, father-daughter, brother-sister etc., not cousin which offers many more gene combination options.
The short term in breeding scheme has been used with great success on Icelandic horses, to give an example, producing excellent horses where up to 90% share the good qualities you've been breeding for, such as excellent gaits temperament etc. truly superior horses.
I would also like to point out that the characteristics you seem to be referring to in your posts is more down to nurture than nature. Even then, a child with the most caring parents can just as well be spoilt and unruly, while one with bad parents could be humble, peaceful and kind. Rather than placing people of such lineage, paternal, maternal, mixed on a pedestal slightly higher than everyone else, it might be more worthwhile to teach everyone to hold such characteristics regardless of background.
I disagree. High quality genes will produce a lineage of high quality genes, if correctly combined. There are always various possibilities, but statistically the combination of good parents will produce a significantly better offspring than the opposite. Mediocre parents, talking horse breeding now, have, on occasion produced the odd excellent offspring, but that's the exception not the rule.
Edit
Also, suggesting that certain genes are more likely to hold personality characteristics means also suggesting that those without those genes are less likely to hold them as a result. It doesn't need much more than that to start talking on the lines of Blood Libel and the 'Curse of Ham'.
Our knowledge of genetic inheritance is still rather crude, and comes from the breeding of animals as for ethical reasons breeding of humans along such lines is not an option. However we have every reason to assume that what holds true in horse breeding holds equally true for humans. Excellence breeds excellence, whether we like it or not. Ideological reasoning has no bearing on that fact.