One challenge many services face when sending emails is that you often want to log a user into the account if they've clicked in from an email – after all, if t

One challenge many services face when sending emails is that you often want to log a user into the account if they've clicked in from an email – after all, if they have access to the email account, they can usually reset the password. But the rub is always the propensity for users to forward on those same emails. If they do, then the second recipient gets control of the first recipient's account, and that's rarely the intention of the first recipient/forwarder. I haven't had a chance to dive in enough, but I wonder if a technique like this could effectively swap tokenized links with generic links (even if you're just swapping 'display' rules) when a message is forwarded. You might have to use different message style/markup output depending on which service you're sending the message to, but my read of this article is that it's not a ridiculous thought.