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As far as the video is concerned I think you are missing he point here.

When using circles as strokes you would employ both edge trailing and edge leading motion.
The regular x-stroke is just as...

that us not how you put an edge on a knife.
Here a very good one that shows exactly how it is done.

YouTube - How to Sharpen a Knife

I have never seen anyone use trailing stroke when sharpening knives. The usual motion is back and forth at ~45* to the stone with most pressure applied on the pull stroke which is edge leading...