Sam the video you put up was nicely done. The guy mentioned the power scalers and I remember those very well.
I have an old hand scaler that has two rows of teeth and man would the scales fly when I used that thing. Also remember fishing knives having a row of teeth across the back of the blade that worked well.
As kids between ice out and trout season, we targeted redhorse upstream of the Amalie on French Creek. We had an elderly neighbor who baked or made fish cakes and always glady accepted a few fish. Before scaling he would submerge the fish in hot tap water then used a spoon. Scales just piled up as he made each pass.
I learned in the late 60s, watching fish being filleted at Erie, and I can not remember ever scaling another fish. I'm sure I've caught a few fish since then, just don't remember scaling them. 😁
Anyway, I'll be attempting some fish tails come this crappie season.
Good times and tight lines.