[B-Con]

Knives are a great example. Any chance it was this guy?

https://youtu.be/pagPuiuA9cY

I've watched like 3 hours of his videos on sharpening because he's pragmatic, approachable, and scientific, and now I actually understand how to sharpen a knife and why it works.

[cyberax]

Yup, this guy. I highly recommend this channel to anyone who wants to learn to sharpen the knives.

It's not at all hard once you understand the idea!