This note in the example is false: "If cfexit is used outside a custom tag, it functions like a cfabort." If cfexit is called from an included template, that particular template halts execution, but the parent template will continue execution (unless you use cfabort instead).
So, clearly cfexit and cfabort do not always function the same when used outside a custom tag.
I'd also imagine there's a good chance that Application.cfc:onRequestEnd() might still fire after a cfexit call, but not cfabort.
I wondered if you new anything about popping a confirmation message when the user closes the browser. I've found the window.onbeforeunload, but this applies to the links within the page. thanks much.