It would be useful to have an option to make use of the email@example.com extension when available.
This provides an alternative to the link/remove rename operation which is not supported on all file systems. In addition, it prevents the scenario where a link is successful and delete fails, leaving two files on the system.
I would also like to officially ask for this. SFTP servers backed by HDFS via NFS Gateway do not support hard links and thus cannot service the rename command. The firstname.lastname@example.org extension provides an alternative renaming method that does not result in an NFS LINK command, but instead, an NFS RENAME command.