"Corner posts should be six foot at an absolute minimum. 8' is much better. After about 10' you don't have to mess with braces."

Let see how can I say "stupid" in a political correct way.  Can't so will just let it go.  Do you realize a 35 ft utility pole is set only 6 ft deep?  The tensions at the top of that pole are larger than any fencing structure.  A single anchor can hold 4 wires from pulling the pole over.  When room for an anchor is not available, a push guy, on pole leaned into the deadend is used to hold the pole.  That is the idea behind the H bracing in fence corners.

6 ft, 8 ft, 10ft holes, what a hoot.  I have pastures where after 2 ft you can either dig the rest of the day with a rock bit, use a little blasting powder, or just set the post.  You are a riot at times Plowboy.