If you look at the actual (kinematic) viscosities, the Sabre is an SAE 40 at 13.5cSt @ 100*C, whereas all the *registered* JASO-FC/FD ols are around 7-8cSt (SAE 20) to suit injector systems.
Even the good syns like Castrol Power 1 Racing TTS are around 7.5 cSt @ 100*C.
Most of the full race oils are 12-17.5 cSt @ 100*C and you still run these at a 'normal' mix ratio, they just give more protection at higher temps/loads/revs.
What advantage are those that are running the really lean mix ratios hoping to achieve ?
It's been shown in testing that more power is achieved with richer mix ratios, all the way up to 16:1, and anyone running the good synthetics and syn blends are getting acceptable to no buildup on pistons and ports at 32-50:1, so what's the attraction ?
I'm not Amsoil bashing, they make good products, but like their mileage claims on car oil changes, it's just marketing.
You'd be mad to extend drains on a car/truck oil without used oil analysis, but you can't do that with a two stroke, you need to go the whole hog with teardowns and measuring everything in a controlled environment, so why try it ?