You guys obviously weren't Boy Scouts... 
Back in the mid-90's, I was checking out Kershaw's newest innovation, the spring-assisted opening mechanism! Never having handled one before (and not knowing what it was), I placed my right thumb on the opening knob and gave it a little pressure. The blade whipped open and locked hard as my thumb (moving in the same arc, but slower) caught up with the blade. I SAW a bit of my thumb fly off and land on the glass display case. Luckily, the shaving was so thin, it did not bleed. It just shaved off a few microns of skin in the shape of one of the scallops in the blade!
I put the knife down, and had NOTHING to do with Kershaw or spring-assisted opening knives until a couple years ago when I broke down and picked up a Chive. However, with the new "flipper" design, it isn't an issue anymore.
Back in the mid-90's, I was checking out Kershaw's newest innovation, the spring-assisted opening mechanism! Never having handled one before (and not knowing what it was), I placed my right thumb on the opening knob and gave it a little pressure. The blade whipped open and locked hard as my thumb (moving in the same arc, but slower) caught up with the blade. I SAW a bit of my thumb fly off and land on the glass display case. Luckily, the shaving was so thin, it did not bleed. It just shaved off a few microns of skin in the shape of one of the scallops in the blade!
I put the knife down, and had NOTHING to do with Kershaw or spring-assisted opening knives until a couple years ago when I broke down and picked up a Chive. However, with the new "flipper" design, it isn't an issue anymore.