Thanks that commit does indeed match my behaviour ... even if it seems a bit messed up all things considered ...

I might use a Fedora Live instance and remove the /home mount point whilst maintaining as a subvolume within root ...

In fact given this behaviour I'm thinking that a bug against anaconda might be warranted to  make home a subvolume (for easy snapshotting etc) but to not explicitly mount it to get the maximum flexibility...

James