[OpenID] relying party delegation?

[James Tindall]

Once a user registers with an RP, the RP could then use the supplied id 
along with the subsequently discovered op_endpoint to add OpenID 
delegation to the user's profile page or xrds - and so enable the user 
to use their RP site page url to log in to other RPs? I guess this runs 
counter to the OpenID decentralization ethos (?) but are there any other 
reasons why this is not a good idea?

=james.tindall