Last two sentences up here are worth reading (remember this whole thing happened post-Snowden [as in Snowden just happened only slightly prior], so there was a lot of scrutiny on them as well as the selected winners).
End Result
"In response to the controversy, in November 2013 John Kelsey of NIST proposed to go back to the original c = 2d proposal for all SHA-2 drop-in replacement isntances. The reversion was confirmed [in] subsequent drafts and the final release."
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