I do not believe this is saying that they need to type in a user name, only that they must have a unique username / password combination. As for the electronic signature in this case this is achieved by combining the two methods below...
- Do not use 'automatic log-in' to ensure Users are validated when they connect to the Vault
- Add 'Authentication' to Transitions that require an electronic signature (e.g. Checked, Approved) - this prompts the user to enter their password a second time
Take a look at this page and the accompanying document.
Customer Support Mangager