Obviously there is tensile stress in the Blade pole setup. That stress is cyclic - higher tensile stress when the spin is not up, reduced or no tensile stress when the spin is loaded. Since the pole is Aluminum fatigue damage will accumulate regardless of the magnitude of that stress. The question is at what rate does it accumulate, which I can only guess at with the information available to me.

However, the failure does not look like it is due to a single overload to me, which leads me to belive that fatigue was a large factor.

The pre-bend or lack of thereof doesn't make a difference regarding the presence of bending moment in the pole. With pre-bend we expect tensile stress at the top of the pole when the spin is not up. Without pre-bend we expect tensile stress at the bottom of the pole when the spin is up.

That's really the entire point of what I've been saying. As I stated, the options I gave are ways to reduce that tensile stress. And yes, they will reduce the tensile stress despite your irrelevant attempts to score points. They may or may not be good solutions for other reasons, but that's a different matter.

If you want to claim that you can model the Blade pole setup as a truss with any degree of accuracy, you are wrong. There is no hinge at the bridle, which fails the idealization. In addition, we know there is a significant bending moment there - enough to cause 2" of deflection at the pole tip - which means you can't ignore the failure of the idealization.

The problem is not statically determinate either. That has nothing to do with whether it's a truss or not - trusses like any other type of structure can be either determinate or indeterminate.

Now, claiming that an actual engineer would model this as a truss plus a cantilever using superposition is bizarre. You can't cleanly split this problem that way, at best you could arrive at a solution iteratively. The obvious and easiest solution to this indeterminate problem is to replace the lines to the end of the pole with virtual forces. A virtual moment at the bridle, which is what I think you are getting at, is only something you would do to prove a silly point on some discussion forum.

Anyway, this has gone on long enough. I belive that fatigue is a large factor in that failure. You don't. Let's leave it at that.