Yes there is a 20/70/10 curve with both the old/new systems, but managers aren't held to the curve until the org size is around 30-50 people so exceptions can be made in either direction for strong/weak teams. Also the claim that only 1/2's can transfer is bogus, plenty of managers are happy to take 3's and 4's can move in most situations (I know of a person who got multiple U-10/5's and he still found a job). Finally the claim that calibration takes a ton of time is way over hyped, I probably spent less than a week on year end calibration (bit more than that including writing reviews, which is hugely important).
As a Software Development Manager at Amazon I can also attest to the fact that calibration isn't unique to Microsoft, Amazon just calls it OLR's. It's not a perfect system, but I have yet to hear great suggestions on how to improve it. I'm also not advocating the Microsoft system, but the facts in the article are just out of whack.