No offense taken. I wasn't sure it was a new idea, just one that I had trouble finding demonstrated anywhere. I couldn't find any simple web site demonstrating just this one single idea, separated from a lot of other issues, so I made this.

Flask-Security looks like a good solution to every new web site having to roll their own code. BTW, It's not clear from Flask-Security that there is a no-password option given that the user model has a password field required.