you mention line breeding. i would provide a pedigree or two and talk about it and include info other than saying such and such a bull is in the same position with a different cow or whatever.
i always think of linebreeding as most of the time as having a LOWER or equal percentage of a sire or dam than the original parents of an animal. it's pretty hard to get 50% of an animal unless they are the same grandparent on both sides of the pedigree. and if you include a sire to daughter mating, include some historical reference like the accident that was ext.
linebreeding is used to fix positive traits, identify and eliminate bad ones with a heavy cull rate. you mention the culling rate, but tie it in with the linebreeding.