TEK, you understand the principles behind the RAT concept. Three core modes; interception, pressure and termination (hate using that word...I prefer the term "resolution").
So what's happening is that Voo was using eye jabs and destructions as his intercept..more or less, right? Then the straight blast as his pressure tactic. After that it was the double neck tie as his delivery system for knees, elbows and the headbutt.
Well, conceptually, none of that has changed really. What's been modified as some of the tactics for accomplishing each end.
Lets start with the intercepts. I don't like the long-range eye jab that Vunak LOVES. I do however like the elbow destruction and use it quite regularly to great effect in the gym. We've all felt it and it hurts, even through 16oz boxing gloves. The problem with teaching that to folks is, those are just "moves". That's a whole other issue beyond what we're trying to discuss presently.
I don't like the eye jab because there is nothing on it. Honestly, I would rather pop someone with a stiff jab than to "flick" an eye jab out. The jab has more on it. Taking a slight step forward into it can disrupt someone's timing, rhythm and footwork, etc. It's just more substantial. Ever walk right through someone's weak jab? People will. If a person doesn't have a jab worthy of respect, a person will walk straight through it. Flicking an eye jab out is weaker than the weakest jab if it doesn't land on the eyeball (which is a small target for a small weapon - in other words, it's hard to hit, particularly if your opponent is hitting you and otherwise has his guard/hands up as well). Thus I've thrown the eye jab out. Besides, eye jabs are easily thrown if you've been working your boxing jab any length of time. I would just rather have a credible, legitimate and verifiable technique (in terms of having seen it land and having seen the results in training). Thus, the jab is an even BETTER intercept as it accomplishes the same things in a better manner.
The "spike" (elbow destruction) is something that I've seen to work. With good timing and out of a boxing delivery system, that is something that I consider "high percentage" (which is the only thing I keep, everything else is thrown out).
So, from an interception point of view, having a decent boxing game is TEN times better than practicing eye jabs and destructions by themselves. If I had to put my money on someone in a fight, I would always put it on a boxer vs. some guy that has been practicing eye jabs. Just me.
The straight blast is "ok". I would personally rather use the modified "boxing blast", but I'm not going to completely throw out the straight blast altogether. The problem with that is again, that there is nothing on it, unless you can run into it full-bore. If you're using it to obtain the clinch, I think it's ok. My only opinion here is that the boxing blast is safer. You have to have more timing when using that because it's slower. But timing is an important attribute anyway and it's worth developing. Thats another reason why training delivery systems is important rather than just learning moves.
In terms of pressure (which the blast is designed to do), one can also use good boxing combinations to do the same thing. Pressure doesn't obviously have to always be "forward". Pressure can come by a disparity of skill and force. In other words, throw good tight combos in the face of someone who can't box and you'll see them fold up like a chair. Thats another form of pressure that comes from having functional delivery systems.
The "termination" stage is simply either chooing to disengage (pretty easily if you're outclassing someone, difficult if you're not) or choosing to "beat on them like they stole something" (to borrow a phrase). Whether that happens in the free movement range or happens in the clinch doesn't matter. But if we're talking about the clinch, I personally want to control at least one arm and the neck, as opposed to just the neck alone. I prefer to have an all-around clinch game rather than just the double neck tie. More options = mo' better.

All in all, it's still fundamentally the same - put some hurt on your opponent more than he does to you in ways which are simultaneously offensive and defensive, as the RAT was intended to be.
In regard to Erik Paulson, he develops "delivery systems" as opposed to just teaching someone a collection of moves. There's a difference. However, an armbar in MMA is an armbar on the street, or anywhere else. A punch is a punch. A shoulder lock is a shoulder lock. You have to have an athletic model of training these attacks and that's all he does. His fighters are more than capable of defending themselves because of his approach. It's hard to argue with athleticism, conditioning, experience and skill.
-John