The μ means micro, so it must be small! ;)

Taking 300μg LSD would make most people quite... uncomfortable. A normal recreational dose is 100μg, so I'm not sure how what this guy has done is in any way similar to microdosing unless he weighs about 1,000 lbs.

What I meant to express is that longterm, small 10-30ug microdoses do have an effect on me, and that effect is largely negative, but that my "sweet spot" in terms of experience is very high. Less that 300ug creates almost no observably "psychedelic" effects; its like a wasted experience with purely psychological residue. And so, following, one would think that for someone with such a high tolerance actual microdosing would have no effect at all; it does, and that effect manifests itself in a sort of unpleasant underlying low-level depression and anxiety.

Small amounts probably put your thought processes into a sort of "uncanny valley," where you can notice something is wrong, but not enough to revel in it.

It's like going outside with your zipper open, rather than with no pants at all:)

>for someone with such a high tolerance

I don't think that there's a tolerance with LSD. There's a learning curve, rather; it doesn't affect you any less, you just deal with it better.