Meanwhile my doc prescribed a high dose, which I take right before bed, no sleep/wake impact at all. Similarly, my SO was prescribed even higher, no "awakeness" impact.

If you're having a reaction before the substance has even made it to your bloodstream, never mind brain, it's likely not due to that substance, but a placebo effect.

That said, continually taking it results in better consistent levels--rendering it meaningless when it's taken as it's always in your bloodstream in sufficient amounts.