Again, due to different camera positions, we can't accurately compare, but this does give some idea of why the second jump was better.
My own thoughts: Edwards goes flat out with the first jump, aggressive and earnest. Having that record in the bank, Edwards appears more relaxed during the second jump. It's almost zen like - turning his conscious mind off, skimming like the stone across the water as he often says himself. His body is more upright, and this is less about using every sinew in his body and more about trusting his technique. The biggest gain seems to be the jump where he approaches it with less reach and in the perfect vertical position to continue the momentum. (I'm not an expert, so just my 2 pence, please share your own thoughts in the comments!)
P.S. Can the IAAF please start using fixed distance cameras so we can compare? Good example is the NFL 40 yard dash.
