Alot of folks draw lines in the sand over inbreeding vs line breeding. I can see how You'd draw the line at the nuclear family to classify it as inbreeding. Some draw it deeper into the extended family.

I think to determine what it is the flow of the breedings behind those dogs should be taken into account. I wouldn't call an aunt to nephew breeding within a scatterbred pool of dogs inbreeding. You'd still be lining things out. What are you really tightening up on in such a scenario?

The bates' Susie dog was lined out a bit, then it was brought back together to culminate in her being produced i.I believe the formula behind her of line breeding lent to her being inbred more so than just it being an aunt nephew. We do tons of 1st n 2nd cousin and aunt uncle and nice nephew and great uncle breedings etc...we never really consider it inbreeding unless its from the nuclear family. All the dogs on the yard are at least 2nd cousins anyway.