There is I think a need to go through the 16 options laid out in Ross' truth table [#]
How we choose to deal with each use case can be decided through that putative design meeting.  
I simply assumed we would take the "create a user" approach and link them all back together - but that has its own problems.  Would need some sensible comments on LocalStorage from Phil/Dak - IIRR there is 5MB limit.  

I am not claiming it is the right function either - that truth table looks like a lot of pain !



[#] I cannot link to this. Am going to revive the gh-pages script and get some docs up. Readthedocs does not like the dependancies in the repo and I cannot work out how to fix it so they do.