Sounds like you're close. I find a visual aid saves on shave tests & guess work. I use 30x Jewellers loupe.
If the scratches are even & all the way to the edge the razor is most likely sharp & should pass the HHT at various stages.
If the scratches are also reduced by polishing evenly all the way to the edge the razor will also be smooth.

Any irregularity in the brightness & scratch pattern indicates more work is needed. Talking bout stuff you won't see with the naked eye.