Circ - Have you tried hovering your mouse over the thread name from the home page (http://www.vehicross.info/modules.php?name=Home)? Doing that shows you a preview of post #1 in the thread, which I personally find makes it easier to decide whether you're interested in a thread or not (correctly categorized or otherwise).

I think if you try using that feature you may find poor categorization to be less of an issue.