Well, for someone who probably has one of the most secure networks possible, I must admit that we have our usernames and a one letter password that everyone knows. I guess I am missing why it would be bad to go in and change make an entry into a note while your partner was logged in. Computer security can only go so far and then one has to rely on just being honest. I always go back to the paper chart when I think of things like this, and what would keep one from charting in a note just done that day.
I think it would be more of an issue if there were more audit trails where logins would be more helpful.