The Ashwin-Buttler thing and Howe's posts are an example of the sloppy thinking particularly with respect to the laws as currently written.
Buttler was not watching the bowler even before Ashwin had entered his pre-delivery stride. He'd probably timed himself on Ashwin's full run-up on the first ball of the over [Buttler was run-out on what would have been the last] and thereafter payed no attention at all to the bowler other than to watch the run-up's commencement. Buttler simply assumed that the same thing would happen without checking whether that was actually the case, which is like expecting all deliveries to move one way just because the first did.
Ever since retaining the ball to effect a run-out was disallowed, the laws have limited the point at which running out the non-striker by defining certain physical actions or positions which the bowler has attained, namely
--- The delivery stride
--- The swing of the bowler's arm
--- The expected release point
None of the laws mention the timing of these particular actions, therefore they must refer to the physical occurrence of them, 'expected release point' referring to a point at which the bowler, having gone through his run-up and going through his bowling action, would normal release the ball rather than retaining a hold of it.
The laws do not in any way state, "where the batsman has made a mental calculation as to when these actions would have occurred".
One could theoretically try 'pull-out' of one's bowling action even as the arm is coming up over one's shoulder to effect a run out assuming one could do it in the correct way: in reality, as the umpire has some discretion under the various laws, it is unlikely a bowler could say he pulled out 50 cm before his release point as the physical action would probably be indistinguishable from a normal bowling action with the ball retained, but this is just hypothetical.
Equally, one can make the physical allowance as an umpire for the fact that a bowler pulling out at the end of his pre-delivery stride will result in him assuming a position that may look similar to a bowling delivery. In the Buttler run-out, some posters here as well as people on other sites showed a picture of Ashwin with his legs spread apart, left foot ahead of right foot and right arm down and used it to argue that he 'faked'. But the results of the pre-delivery stride (the 'jump' or 'cross') mean one will end up with one's legs in that position no matter what if one tries to stop before bowling, and the right arm was down so he could actually break the wicket. At no point had he actually begun to swing his arm over like he was actually trying to move the ball down the pitch.
The laws do not give space for the expectations of the batsman based on his judgement alone as to when he can move off.
