I've seen the "sparklies", not a sign of the bevel not being set, but definitely something going on with the edge. I've seen it on razors
that were deeply pitted and the pits became revealed in the honing. I've also seen it appear out of nowhere on a blade that had looked
just fine. I rehoned that blade yesterday and now it's fine. I suspected at first that stropping on linen too forcefully might have caused
it, but I'm not sure. I'll do some experimenting on linen if I see them appear again. Great subject!