Ask the browser... There's extensions in some browsers (Chrome and Safari IIRC do this) that will allow the detection and (Accurate and consistent) reporting of page load times.
Failing that use firebug on firefox, or httpwatch... But without a lot of help from the browser itself, you have NO idea how long it takes a browser to load a page. (Because you need to consider rendering time, and take into account the fact that you'll have multiple connections as you've found out and that also connections are left open for 'a while' after they've been finished with.
H
Nimbostratus
