I could see a variation of this request being a surrogate (like someone's EA) to edit on your behalf. Perhaps the permission is universal for an Admin role but also each user could enable or disable having someone act or edit on their behalf.
+ 1 As an ADMIN, I would love this! There are times that Managers are giving Demos and create 'test' entries - and later ask me to delete them. In order for me to do so, I have to log in as them - it would be awesome if I could just stay under my profile instead.