(Just got an email about this reply today. Quite a delay)
For better or worse, I believe, people are used to the username/password/signup/login-flow. So when trying to teach them a simpler/better way, I thought it might be an advantage to make it look like something they might already know. Permalinks and short links are common ("permalinks" was at least common for blogs in the past, and "short links" became popular with twitter and its artificial length limitation and are still found on e.g. youtube), so you might make it look like something the user knows (and doesn't find scary) by using those terms, since the functionality is actually the same. The only reason for the extra option to send the link as an email, would be to let the user use the mail as a reminder. The only real difference between such a flow and the ordinary username/password is that the site doesn't get a "validated" email, which can be used for "spam" the user.
The title "Sign in and registration" is unfortunate because it's all just sign in. However, I still feel uneasy about it. People might think "Oh. That's where I go to log in, but how do I register or sign up?"
By the way I don't understand what you mean by "-link that presented a perma/short-link". Can you elaborate what you mean?
Comment
(Just got an email about this reply today. Quite a delay)
For better or worse, I believe, people are used to the username/password/signup/login-flow. So when trying to teach them a simpler/better way, I thought it might be an advantage to make it look like something they might already know. Permalinks and short links are common ("permalinks" was at least common for blogs in the past, and "short links" became popular with twitter and its artificial length limitation and are still found on e.g. youtube), so you might make it look like something the user knows (and doesn't find scary) by using those terms, since the functionality is actually the same. The only reason for the extra option to send the link as an email, would be to let the user use the mail as a reminder.
The only real difference between such a flow and the ordinary username/password is that the site doesn't get a "validated" email, which can be used for "spam" the user.
Parent comment
The title "Sign in and registration" is unfortunate because it's all just sign in. However, I still feel uneasy about it. People might think "Oh. That's where I go to log in, but how do I register or sign up?" By the way I don't understand what you mean by "-link that presented a perma/short-link". Can you elaborate what you mean?