[safisher]

Originally Posted by Langy

RAW GURPS has no way of silencing your victim

Ah, but that's not true. MA: FCCS explicitly deals with this.

he can still yell for help even though his neck was just cut in half, and he'll still take forever to die from blood loss even in the worst possible situation.

That's pretty much up to the GM. First, it's pretty difficult to yell, when 1) your mouth is covered, and 2) your windpipe is severed. GMs are free to treat that how they want. Further, if a successful sentry removal attack hits you it's a good chance you'll be surprised (mental stunned) and then you'll quickly be in shock as you bleed out (shocked and stunned via a major wound, perhaps multiple ones as the attacker keeps stabbing -- and assuming bleeding rules are used, you keep bleeding). In addition, there are rules for fright checks for wounds.

All of this, I think, indicates some impairment to either the ability to yell, or the capacity to decide to yell.

Also: I had thought a large knife was something a bit bigger than a combat knife (more along the lines of a machete), hence why I used a small knife in my example.

No, large knife is a typical military issue combat knife.

The All-Out Grapple and Strike maneuver (which I had completely missed) also looks like it'll be much more useful for this.

Yes.

then all right, sentry removal isn't as badly done in GURPS as I had thought. I still think that you should get a bonus to hit a location that you've immobilized via grappling, that severe bleeding is too slow, and that there should be some mention in the RAW that grappling the jaw silences a person.

There's a difference between your opinion, and not understanding the rules as they currently stand. All too often, the problem on these forums is the latter.