Why is that none of the commentators realise what Froome and Brailsford did yesterday with the timing of the bike change? It seems obvious to me that they were indulging in a tiny but important piece of psychology - by changing just before the second time check, it would make it look to Contador ahead that Froome was down on him, and allow Froome to disguise his real pace (which was already level with or quicker than Contador).
Rob Hayles said exactly that on the 5-live commentary at the time