Yes, there's probably a more or less foolproof way to implement it. If you really want it, I'm not opposed, but I still don't see why.
Opinions are welcome and if this is not a good feature, then there is no reason to add this.
BTW, what happens when you uncheck the box "Hide email address from public?" in your profile-account related settings? Isn't that what you wanted?
No. That will display the email address I linked with this account but I don't want to use that email address. Especially, because of the potential spam.