One topic not discussed in the article is transfers.
When transferring a domain from one registrar to another, most receiving registrars ask you to Unlock the domain and remove Whois Privacy so they can communicate directly with the Registrant's Email Contact during the transfer process.
Should a prior Whois Privacy email (from the original registrar) be transferred to the new registar as the Registrant Contact Email, the problem becomes the original registrar cancels the forwarding. Oops! Dead end email in Registrant Contact Email could lead to a domain registration being canceled down the road should they be unable to reach you for verification purposes.
So.... how will this play out for domain transfers when implemented?
My gut... it will be a confusing mess the 1st 90 days after implementation and we (as domainers) might find it difficult to transfer domains to a new owner (buyer).