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Precisely. It is an identical technique being used in a different direction.
Those two diagrams are the same one. Only the viewpoint has changed.

The scythe analogy has been used to describe a...

Unfortunately there are two different methods that are called scything - the one you describe, and this one:
http://straightrazorpalace.com/shaving/30594-finding-right-angle-2.html#post313829...

Scything works best when you do it subconsciously IMO. The skill is picked up without even realising it.

I think you word it well when you say that if you aren't scything, you are scraping. But...