I know of a couple who has a 'One Shot Wonder' rule.
He is infertal and she is a knockout. They have no problems with interracial mixing.
This is their rule: They screen the Bull for health issues and perfer that he has already sired children. On the Ovulation Day, the Bull is invited to a hotel room, where the 'insemination' (Amazing Breeding) takes place. He has one opertunity to be with the Wife, but may inseminate as many times as he desires. It's usually all night or all day long. Then, he leaves, never knowing their real names or addresses. Never to inquire as to his potential fatherhood.
This method has already worked. He was already the ******* of 5 children; now he has a 6th (that he will never know about) The pregnancy went well and 9 months later a health baby was born. Gave the maternity ward a bit of a shock when they saw the coloration and realized that the spouses were fine with it; they were actaully extactic about having a baby, finally.
Why the One Shot Wonder rule:
It protects everyone involved. The Bull gets to impregnate, but has no responsibilities after. For the couple, there is no cost of a sperm bank, they control the insemination process 100% in an act of lovemaking. The couple's bond is protected as there is no chance for another encounter or a bond forming between the preg wife and Bull. The cuck is protected, he gets to set up and participate in the 'act' of creating his baby, but has no worries his wife will form an attachment. The baby is protected in that the ******* is 100% checked out and will never be able to interfear with paternity challenges.
I know them, and they seem to want another baby in a year or two. (No, don't ask me, I don't screen for them)