From My very limited test, that is pretty much my conclusion as well.
I was surprised at how deep the scratches from the the 36 grit were. It might take two passes from 80 and 120 to remove them. My point is to be careful on very thin stock or you will end up with nothing but dust.
Those scratches were deeper and worse than the ones left by my band saw. Just length wise rather than across the grain. But if you find them satisfactory for gluing to a substraight, they would be fine.
The bandsaw cut off a WoodSlicer blade were probably good enough for gluing veneer to a substraight, if the veneer were thin enough to allow the very slight flexing to accommodate the waviness. Out of an abundance of caution I would probably sand it anyway.
A better test would be to sand an end grain cutting board. Just made a couple. Sanded them with my bigger dual drum Grizzly sander. A completely different beast. The drums rotate pulling the work forward and the tiny little motor that drives the conveyor RESISTS the pull. I recently fired a cutting board through mine so hard it put a foot long crack in the side of my Herby Curby trash can. The machine has a tiny little picture on it waring you not to stand in front of it, a mistake you will only make once.
I used my homemade belt changing tool. Worked well. Wonder if a real one would work better? Thanks for sending me the picture.