Have you used a knife?

[Bammx2]

I got to thinking about brothershaws question on pulling a knife and I came up with one of my own.
It's along the same lines.....
But what I wanna know is; who has used a knife in a combat situation?
Be it defensive or whatever...
I know alot of us train for the "what if's" and "just in case" scenario's;but I am curious if anyone actually has and what prompted it......?????
what was the deciding factor for "go time"? what was the "point of no return" and what was on your mind?
I do NOT want gory details!
I am interested in a psychological point of view only.
Not actual techniques.

 

[MA-Caver]

I've been in several knife fights while out on the streets. I've got the scars to prove them as well.
The psychological effects? Whoo, they're something else I'll say that.
When their blade cuts/stabs you it's a struggle not to go into shock because of the sheer violence of the act and the results. The first time, I got sliced on the arm and was damned lucky not to have my vein splayed open. I nearly got my throat cut in the bargain when the guy slashed back at me again because I was staring at the blood coming out of my arm (there was a hellva lot of it) and someone cried out and I looked up and jerked back in time to avoid the next slash and got back into the fight. ... no winners BTW... cops showed up and we had to skee-daddle to the four points of the compass.
Second time, I was stabbed unexpectedly in the gut (right lower abdomen) and manged to recover enough to fight because it didn't hurt (later yes) and I thought the guy had merely punched me. No I did not get hospitialization because of the nature of the "fight" and the reasons (being illegal at the time) thereof.
Psychologically it scares the hell out of you the first time it happens. Enough to incapacitate you to death.
When I used my blade for defense I had already psyched myself up enough not to be affected by whatever happens... also at the time (a low point in my life) I was mean enough not to care. This is a kinder, gentler MACaver writing this now.
Psychological you ask... using it I was hoping to create as much damage as possible and scare the crap out of the guy while doing it. It puts an end to a fight real quick.