It assumes a market principles that have not been proven just hand-waved by neo-classical economics. 1) it assumes that fuel purchase is something that scales with price. ( Oh gas is 10% cheaper I will drive 10% mores).
2) It assumes full knowledge and rational actors. (the twin inanities that prevent economics from being anything but a pseudo-science). a. fuel is what is known as a grudge purchase. if I have 100 miles I need to go I buy 100 miles worth of gasoline to do it. Mostly independently of price and certainly not smoothly graduated.
b. fuel costs (in currency) are fantastically low for shipping a 10% dip in demand would be expressed as not enough to care about.
As to your point 1a, I very much enjoyed the economists reactions to skyrocketing gasoline prices back in 07-08. At that time gas went from something less than $2.70/gal to about $4.15 in the space of one year. Every day on Marketplace some other bonehead would be head scratching and ad hoc-ing about why people weren't driving less. I believe that above $4, there actually began to be modest decrease in driving distance per consumer, but then the economy tanked and gas fell to nothing so we were never able to see really long term data. Whatever the case, there is certainly little or no elasticity in the price of gas.
it is just speculatin' dressed up with math.
I had a working economist tell me that checking for normalcy of distributions was a waste of time because "economic statistics is far more sophisticated then that used by biologists and physicists" he also told me that doing derivatives of discontinuous functions was "normal" and done all the time by "scientists".
Neo-classical economics passes both the Popper and Latakos test of being pseudo-science
it is not falsifiable and does not predict novel truths that turn out to be true. Bah Humbug.
:) Although in the larger economic field there are quite a few very clever folks doing good work.
I think that is the point I made that ended our correspondence. The scary part is that these guys write policy, ruin lives.