My personal take-away from O.P.s "A Challenging", "But Valuable", "Growth Opportunity"?
Never Ass-u-me the Other party will do what "I" Expect. Most Specifically when "I" am ABSOLUTELY, 100%, CERTAIN there is 'Only a Single, Isolated, Outcome Even Possible'.
... Complacency + Inattention + 100s of Pounds of Metal Can Kill.

... In this particular case: Always Signal the intention to turn, Always Do 'My Best' to Insure All Other Drivers Understand My Intention to Turn.

... More generally: It is 'My' Responsibility to those that may Love/Care/Depend upon me to ensure 'My' bike handling skills are such that "I" can confidently, reliably, proceed and accelerate Safely thru the ENTIRE intersection with one arm completely outstretched, indicating my intended direction to All Other Road User's AND WITNESSES if necessary.


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