(http://i890.photobucket.com/albums/ac105/dbma4eva/UFC129-EllenbergersLeftHookSetup1-sg.gif)(http://i890.photobucket.com/albums/ac105/dbma4eva/UFC129-EllenbergersLeftHookSetup2-sg.gif)
I may be over-thinking, but think that Jake Ellenberger was testing Pierson's peripheral vision with his left hand move after the parry of Sean's jab... once the left hand reaches a certain point, Pierson won't pick up on it without moving his head, but once he does that, the right may be coming so he doesn't move the head... and Jake launches a left hook out of Pierson's peripheral vision... don't think I've ever seen this before.
Left Hook KO gif coming...
EDIT:
(http://i890.photobucket.com/albums/ac105/dbma4eva/UFC129-EllenbergersLeftHookKO-sg.gif)
Yeah, congrats VM!
My thanks to my friend K-Dub-T for posting this gif... not my gif, props to the gif maker.
(http://img.mixedmartialarts.com/method=get&s=randy-couture-lyoto-machida-gif.gif)