I hear ya Dane... And agree.
I take the Blooding of my Tools and Weapons seriously...
I charge All of my weapons, Blade, Bow and Firearm with my own LifeBlood.
Always have even as a child. Superstition? Maybe... But it has worked for me.
I think the saying of which you speak refers to blooding someone else's weapon.
Or perhaps a weapon built, charged or used under questionable conditions...
I also soak my Tools and Weapons in the light of a Full Moon.
And Cleanse Tools and Weapons in Earth.
I burn Tobacco and Pray over my Tools and Weapons as well...
Who's to say?
Guess I won't know the truth of it all till I step into the Next World...
Maybe...
-gus