I've fallen down a bit of a rabbit hole!
I've been thinking of ways to get a powered fret-slot cutting system going, both for speed and consistency of depth. I'm not quite ready to invest in the StewMac table saw blade, especially since I'd prefer to have a dedicated system rather than have to change blades in and out, so I've been looking at options (I'm also not ready to have a dedicated table saw JUST for cutting fret slots!).
One I've seen is the Mighty Mite mini benchtop saw, but I've seen consistent complaints about the power.
However I watched Del Puckett's video on YT about using the saw, and noted two things:
1. He says he's able to get it to work just fine for cutting fret slots if he runs the fretboard over the blade quickly, rather than slowly - if he goes slow, the motor seems to grind to a halt. This appears to be what folks are referring to when they talk about the motor being underpowered.
2. This part seemed important: he mentioned that he replaces the stock blade that comes with the saw with a super-thin ....
In the course of poking around on the net I found this post by Bruce Johnson on talkbass.com (about a quarter of the way down the page) about this exact question and one thing he noted is that most woodworking table saw blades have a "set" - which is to say, the width of the kerf at the ends of the teeth is slightly wider than the rest of the blade, giving it a kind of "Y"-shaped cross section; this is to reduce binding as the wood heats up.
Importantly, metal-cutting blades like jewelers blades do NOT have this "set" - the sides of the blades are completely parallel.
So it occurred to me - if everyone using the Mighty-mite saw with the jeweler's super-thin kerf blades, those would not have the "set" and would be likely to bind when running the fretboard across the blade at low speed. This would explain why it seems to work fine if you run the fretboard across the blade quickly.
It would seem the solution might be to find or modify the super-thin-kerf jewelers blade to have a slight set to give the sides of the blade space?