[Double Naught Spy]

So my question is whether a 125 lb woman wielding a knife could overcome this level of armor?

I am still trying to figure out the relevance of the woman's weight here, as if weight determines strength somehow.

While a vest may be able to stop X amount of ft lbs of energy, that is only part of the story. That energy must be captured by the fibers. Pointed implements allow the implement to get between the fibers and hence the fibers have trouble stopping the implement. So, a person with a blunt butter knife probably won't penetrate a ballastic vest when thrust by a person, but ice picks, pointy knives, etc. could be.

IMHO if you find yourself in the situatiion that you are facing a determined, well-trained knife fighter, even with a gun you can die before you clear your holster.

Interesting quote. Not very enlightening and maybe not accurate, but interesting. The sort of rule of thumb is that a person with a knife who is within 7 yards can close the distance and stab a person in 1.5 seconds, sometimes less, and 1.5 seconds is faster than the speed most people can draw their firearms, police from secured holsters or CCW people from concealed locations. This isn't necessarily a well-trained or particularly determined adversary. Of course, the draw time can be shortened if the intended victim perceives a threat and is prepped by doing things like already having a hand on the gun to be drawn.

As a clarification, a well-trained and determined person overcome a person carrying a gun in a whole manner of circumstances and with a variety of weapons. There is nothing particularly special about knives other than they can penetrate typical ballistic soft armor. A well trained and determined person could overcome a gun carry with something as common as a rock, golf club, baseball bat, stun gun, etc. etc. etc. The smarter well trained and determined folks will simply strike without warning.