Ray,
While this is a valid workaround, which we have tried. But its confusing for the end user and they sometimes fumble with the alias format and lose out account access, creates support overhead etc.
The need described by kama is similar to facebook pages or YouTube channels – they are a social network with members having profiles but also multiple members can manage a page or a YouTube channel.
Typical use cases for VIP members who May want their assistants to operate and update certain sections of their accounts without giving away the credentials of their account. The VIP user could allow read/write permissions to certain sections of the profile. For e.g. my assistant can edit my profile, but not read my private message’s or change my subscription type