Link prefetch in Book module

While we were testing we found the counter increment for book pages not happening properly. It increases count for the next page. After a few hours of debugging, we found it only happens in Firefox browser, due to LINk being added with rel="next" (by book module) which make FF to prefetch the next page content for better user experience. Not sure about other browsers. FF send X-Moz request header during such request, Safari sends X-Purpose (not sure). Do you think you need to take this into account and prevent incrementing counter? This may apply to web crawlers. We can check the HTTP_USER_AGENT in such cases.