Improved fuel economy with taller 5th gear
It's really a matter of the engine's torque curve and at what MPH the flat part of that curve will be achieved. Typically, engines provide optimum mileage in a range of the curve which appears rather flat, like a stylized mesa.
As for it's utility in the 'Stans . . . well, that will be interesting. Not alot of roads like that, there.
With so much else to watch for . . . roaming livestock (horses, yaks, bactrian camels, goats, etc), road conditions, the ever vigiliant revenue generation officals (aka 'police'), scenic views and signage in cyrillic . . . at least in UZ, it's a lot more critical to SEE a fuel station WITH fuel than optimize on your current usage !
Orange, it's the new black.