Many tricks don't work best in all wood species/states like cheap/fast growing/thus weaker in trade/punky/weed species or otherwise compromised woods that overload before loading all of helpful force trying to get.
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In Murphy's original vid, i see a faux weakness of extra cut that closes, and then a close of a Step Dutchman.
Any close changes pivot point, taking leverage from load side and giving more to support side>>effect depends some on rotation position of spar
>>1st close is across flex angle of fiber for now firmer flex (started with less resistance)
>>2nd Dutchman close as dead push up fiber column and a more severe, uncompromising change and sudden pulse in leveraged support increase
(but is to one side, so offers other open side of face as path of least resistance, and pivotal change in leverages especially early in fall.
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>>LET'S MAKE MORE/THICKER!
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To theory of all hinges for same load support from same pivot line force the same strength hinge resistance to folding forward
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To theory of spoofing faux support need by temporarily spoofing higher load:support ratio, to then quickly amend back to normal after more hinge strength forced
>>Yin-Yang do this by spoofing load or the equal/opposite: weakness to fake extra support need to get thicker hinge
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Working on drawing of :Any close changes leverages, full face dutchman vs. step dutchman. Close across fiber for re-flexxing hinge or close down fiber column for push back of Dutchman force.