You have to account for .040v....how is this confusing? I get the exact same drop and droop as you and out of the 20 775 boards that I've owned this is easily top two, number 1 being the DFI TR2SB+ X48. As for your memory performance, use turbo performance mode on the EX58, it'll tighten up a bunch of subtimings and give you better results.
The Vdoop is not the problem, im a defender of the Good Vdroop
The strange issue is that we have the same real voltage from 1.4000 set in Bios to 1.37500 set in Bios. When down a notch below the 1.37500 i see 1.228v in load in ET6 and Cpuz, from 1.37500 to 1.4000, i see the same load voltage: 1.244