Indeed people tend to define microdosing as a dose without a mind-altering trip. The benefits largely come from the trip itself, rather than the trip being a side-effect, so this could be a fruitless venture. I think it is obviously silly that people expect to be able to divorce the effects from the trip. It is still an extremely interesting question to ask what effects come from small sub-perceptual doses of psychedelics.
>The benefits largely come from the trip itself, rather than the trip being a side-effect
Well, that hasn't really been scientifically established, has it? It could simply be an illusion - just because I had a transcendental experience, then I woke up the next day feeling amazing, doesn't necessarily mean the transcendental experience caused me to feel amazing. No doubt there is some truth to it, as people report all kinds of life-affirming revelations that persist when sober, but we shouldn't exclude the possibility of psilocybin as a therapeutic drug in the traditional mould.
An experiment I would like to see is whether the positive after-effects of a macrodose are still measurable if the subject is unconscious the entire time. Helpfully, this would also blind the study, although a possible confounding factor is that medically rendering someone unconscious has after-effects of its own.