Not at all the discussion I anticipated from the title

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I don't generally put very much thought into how much effort a task requires versus how much energy I have to invest in it in quite the way you describe. If I am seriously planning something out, such as a permaculture design, then I will try to include all sorts of things in my calculus, including how much work (energy) a task requires. Given multiple ways of accomplishing the same goals within a design, the one with the lowest work threshold is a likely winner. As you say, it's a matter of efficiency.
How I handle being stuck in traffic depends more upon my general mood than anything else, but when I am able to think rationally I choose to relax and try to enjoy whatever is there to enjoy, rather than fretting over something beyond my control. Sometimes I may be wound too tight by other circumstances for me to be able to relax, stuck in traffic unable to get to that critical appointment, for example.
And on a day to day basis, just doing whatever around the house - I almost never think about it in terms of energy cost. It is all just stuff that needs to be done whether or not I am up for it.