I had the privilege of actually being there to see Vinny hit that twister. I personally think he wanted it because Eddie Bravo, Scott Epstein and Denny Prokopos were in the audience. You can here them chanting "TWIIIISTER TWIIISTER" before he gets it.
I don't think the finish was the dope part. I think it was the set up. He wanted to hook the arm but Rodrigo did not want to give it to him. So he sold the banana split instead by putting his hands on the shin and ankle - all the while wanting the twister. So the art is in the sell, not the execution.
I also had the privilege of rolling with Terere while in Rio. During one of our rolls he sold the hell out of an open guard sweep. I was tired of being swept by the guy so I defended by promptly shifting my weight to avoid it. Then he PROMPTLY swept me the other way. Then he said "MOE THAH FOE KAH!". I laughed so hard I almost could not continue...but I digress...
In my opinion, this is the key that separates the average from the elite. This is the chess match. This is what we are aiming for when we get on the mat. We do not want to force the position, we want it to be given to us via setups.