RG Last Call was on 2017-07-21 for the -07 version. There was support on the list for publishing with clarifications. By the -10 version, those asking for clarification were satisfied. There was adequate review on the mailing list and contributions from people not active in the CFRG.
There were implementations from the -10 version that pointed out some places where the document could be clearer; this resulted in -11. There are now multiple open source implementations of the spec, including ones by the authors and by Cryptech.
A comparison between this algorithm and the one that was earlier published from the CFRG can be found at <https://eprint.iacr.org/2017/349.pdf>.
This draft creates two new IANA registries. The draft also has an IPR disclosure of a US patent whose priority date indicates that the patent has expired.