Scenario - TwitterAppA has an oAuth - TwitterAppA has as part of its functions an embed from TwitterAppB which also uses Twitter oauth
The goal is for users to be able to oauth with TwitterAppA and then be recognized automatically as the same user by the embed of TwitterAppB. Without this the user gets quite confused as they don't understand why they have to login multiple times on one site. Allowing for that functionality would allow all the TwitterApps to begin working in concert to meet user needs which makes the whole community far more effective. I realize though that it does open the door for some security problems. However, it seems that Twitter could maintain a graph of which apps were embedding which other apps in order to allow a trusted relationship model.
