I would have to say that, despite the comments of the MCC and Ashwin himself, having looked at the footage I can say without a doubt that the ball should have been ruled dead by the third umpire, as Ashwin had pulled out of his bowling stride before taking the bails off. Had he continued in his run-up, Buttler would not have been out of the crease by the time the ball was released. That said, I do accept that a batsman should be liable for attempting to take an unfair advantage, but in this case I do not think that Ashwin did the right thing.
What are other peoples' thoughts on the idea of 3rd umpire over-ruling on-field calls for things like overstepping? I feel like there have been many cases lately of outcry over an incorrect decision of this sort, and I wonder if it would be better to have the 3rd umpire ensuring that all of these decisions are correctly made on the field.