Many people believe that a low Coefficient of Inbreeding makes for healthier dogs and strong line breeding weakens a breeding population over time. While this is true for a total population, it is harder to say that it is true for an individual dog.
Linebreeding has its advantages. It cements characteristics in a dog (good and bad) and you have a higher chance of having a consistent litter where you know what you are going to get. When you out-cross, it is anyones guess what parts and characteristics a dog is going to get. Many people like to linebreed, cement qualities and then outcross to try and introduce new or different qualities.
Anymore it is most common to see a COI between 5-10 in most show/performance bred Poodles. When I start seeing COI in the 20s and above, it makes me go
You have to consider the overall health of the dogs in a pedigree. Did a particular dog have a reputation for producing healthy puppies and for living to a ripe old age? Well then linebreeding is not such a bad thing! I might be willing to see this dog 3 times in a pedigree. But..... 5+ times. Not for me.
Conversely, if there is a dog who died of Bloat at an early age or who was known to produce Addisons then I shudder to see him even once. I would take a pass if that dog appeared 2 or more times.