GQ. My first post on this thread was to counter your statement that Vy & Vx and anything to do with them was "crap" and meaningless; I maintain you're wrong.
My scenario was based entirely on needing best angle for a climb, and that by using an appropriate min-drag speed (effectively Vx in a jet) I could achieve my goal. Same scenario, but flying at any other speed used a longer ground track. My scenario was extreme; any noteable tailwind during the 25 minute climb had an adverse effect.
You keep referring to rate and power - if you knew and understood the theory you'd know that these are not relevant to best angle climb, they are for best rate.
You state:
Even when you are OEI you still may get a better rate at a higher speed because the remaining engine produces a bit more power and you use less rudder so there is less drag.
So you acknowledge a speed/configuration that will give you a greater RoC than flying at Vfto; correct, Vfto is best angle - fly faster and you probably will get a better rate, but not the correct procedure when terrain is still an issue.
If you are indeed a Global Express expert I doubt you've ever looked and studied the Vfto graph. Vfto is not best L/D, it is approximately min-drag! Ask your instructor on your next Recurrent to explain why you must climb at V2/Vfto to get above safety alt when OEI.
If you've time to spare in your Global in the cruise why not refresh yourself on the theory and hence differences between climbing at Vx and Vy, you may well learn something that you presently don't appear to understand. And if you choose not to believe they are relevant, then kindly refrain from telling other aviators to ignore them until you demonstrate that you fully understand the theory.