Factoring coffee breaks into web stats.

It's not at all difficult to measure the amount of time that a student spends on a page in the web site of a course. It's probably also not particularly difficult to program a pop-up response after a certain amount of time:

You've been on this page for the past 25 minutes.
Have you encountered a problem that needs somebody's help?
Click if you do.

It's my guess that in situations such as lengthy stays on a particular page the student is simply taking a nap, is perhaps taking a shower, or has even left the computer open but gone out for the evening. Whichever, the offer to click for help isn't going to generate a response.

Go to: Sort of a captive audience, or
Go to: Still running it up the flagpole