At the risk of jumping into this thread mid-stream, I think you are considering the net forces on the spoke, while what you referenced is only the additional sinusoidal force applied as the loaded wheel rotates. Clearly when the wheel is built there is a tension force on the spoke. What I get from what you quoted is that the tensioned spoke acts as a column WRT to the ADDED compressive force so when considering the effect of the compressive force, treat the spoke as a column. Again, it says nothing about the net force, which has to be tension.

scott s.
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