Carl,

You are pointing to a study that was published in 2006. This means the actual data is at least 7 years old.

Can you find a more current example?

Exactly! In fact the change to green out of the ordinary lack of it might make them think something is WRONG, not better.

These are users who also keep their browser sessions going forever and therefore session cookies never expire - thereby making what was supposed to make something more secure, exactly the opposite.