RPGs and doubling scales

[Morrus]

So what exactly are the powers of 2 used for, other than a general sense of "X + 1 is twice X"?

You had two examples: the weight of the car (log base 2 of 1500 is between 11 and 12) and a millionaire (log base 2 of a million is about 20). But what are the units for Agility? What's the agility required to do a back handspring over a car?

Or is just estimating? E.g., a typical human (5) can't really do a back handspring, so maybe it takes a 6 to do a normal back handspring on flat ground. A car isn't THAT much higher than flat ground, so twice as hard again feels about right. Therefore it's a 7.

A back handspring over a delivery truck, on the other hand, is an 8.

Is that the gist of it?

Well, it’s all very right and half-formed, so don’t expect any definitive answers! But maybe it might be Agility vs an objects’s Size to acrobatically bypass it?