I would say a fence encroaching over 2' on a 2 acre lot might be de minimus, but a fence encroaching over 2' on a 25' by 100' lot would not be de minimus.
But that's just my opinion, we will have to wait and see what a Judge thinks.
Right, you put the wire on the pasture side, not the cropland side, if the typical use of the land is such.
Let me ask the question another way. Suppose somebody calls you to survey out a new parcel "back to the fence". What feature of the fence do you measure to?
I have been asked to use an existing fence as a partition line. I use the center of the corner post at the ground as the corner with an offset monument, the owner considers the fence as a straight line, so do I. Have done several this way, but this was one owner dividing his land. Need to look at conditions and the calls for a dividing line between two owners if a fence is called for but would take a strong argument to use anything but the center of the corner post at ground level with straight lines between, even if there was a large kink because of construction ease. Don't think a hard and fast rule is in our best interest, as always it is local conditions and research which includes talking with owners. Sometimes you just need to stick you neck out and call it, of course I am talking about an informed and defensible call.
jud