Getting a PV
175/.66 + 80/.66 = 386
175/.73 + 80/.73 = 349
Getting a KT
260/.66 + 40/.66 + 80/.66 = 575
260/.73 + 40/.73 + 80/.73 = 520
If you are still gonna theorycraft with fuel convertion, again, mind you do it rightly.
Well first off, since strategic points and caches do in fact give you .66 (or at least almost exactly .66 since it's only rounding up from 1.98 to 2) if your not working off fuel points then OKW really is actually getting the amount of fuel it's supposed to, but the reason OKW get's 5 fuel from fuel points is that they get 4.62 fuel, but the game can't do fractions so it rounds up.
And are you suggesting adjusting fuel income is theory crafting? Because it is literally how teching and build times are balanced. The reason why the Schwer is 80 fuel is because with the income disability your paying the same (or close to) Soviet t4 or t3.