Does back dragging when filing dull the file?

[REK Knives]

Interesting video and test

 

[Stuart Davenport Knives]

I saw that one, or one like it, some time back. Pretty interesting results. It seemed to have no effect and IIRC slightly extended the life of the file.

 

[Bill DeShivs]

It hurts nothing at all.

 

[Blankblank]

Yeah. It's fine. I know the old machinists will have a heart attack if they see you do it. But as far as I can tell it makes no real difference.

Also I've seen that video. Very interesting.