Avoidance of risk is avoidance of opportunity. Many farmers prefer to adopt a policy somewhere in the middle, obtaining a few daughters of the bull, but not using him as much as they would use an AI sampled bull. The following is my personal philosophy, forged through several years of watching bull proofs change with addition of more daughters. I believe that NO bull is risk free enough to use on half or more of the herd, at least in Holsteins where many attractive alternatives are available. I further believe that good bulls should be used heavily enough to leave several daughters in a milking string.
Breeder proven bulls present a problem.
This could remove the randomness associated with AI samplings and makes the bull proofs less stable even if Reliability was equal to that of an AI sampled bull. Such concern with daughters of sample bulls by private breeders does not necessarily imply fraud. It only means that daughters of such bulls get a little different attention than daughters of AI progeny test bulls in cooperator herds that don't care which bull makes the grade. In larger herds, I would use him for 30 to 40 services, which should produce about 6 to 8 replacements. Some privately proven bulls will have Reliability values of 0.70 or even higher.