The reason its seems to be counter intuitive to you is that you think BSFC is lowest at low load. The truth is it's the opposite. BSFC is lowest at full load. Just study a BSFC chart. I'll link to the Prius because it's a very efficient engine to begin with:
That said some cars are better than others at cruise.
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Vortex generators are old tech. My new and improved vortex alternators are unstoppable.
"It’s easy to explain how rockets work but explaining the aerodynamics of a wing takes a rocket scientist.
