I think a lot of this depends on the locale of the breeder.
This year I am doing two line-breedings.
My black litter is a Rocket Man grand-daughter bred to a Rocket Man grandson.
This is a pedigree repeat of a litter I did a few years ago [the dam's sister].
I expect I will get theW same kind of litter… and am hoping that to be true... only in all black... and as before, from two p. fanconi clear parents.
My seconde line-breeding is a Benny daughter bred to a Benny grandson. I hope that I get what I am expecting... and I am fairly certain that I will get lots of good stuff. I picked the male based on the characteristics she needs help with, and vice versa.
Now, I know that these breedings couldn't be done in many countries because of the COI. I don't have to worry about that in the US, so am taking this opportunity to do such breedings.
While I like the strict rules [though some I think are quite lame] imposed by other countries, I don't like the COI rules, as most pedigrees from those countries are full of outcross after outcross. That just lends to further inconsistencies in breedings, where line breeding can set a type for the future of a breeding program.