I have an intranet site where half of the pages use jQuery, and ~20% use jQuery UI. Users who navigate the site will almost certainly open a page containing jQuery UI during their visit.
What I'd like to do is use for all pages a standard template that includes calls to jQuery and jQuery UI. It would make the site maintenance easier, but it also means that for 80% of my pages jQuery UI will be loaded for nothing.
What I have been told is that I should not worry too much about that. Calls to jQuery and jQuery UI will be cached by the browser, so anyway they'll only be called once during the user's visit.
Is this correct? Or are there other performance factors that could make the systematic call a bad idea?