@Giancarlo: is that supposed to be a troll? Not very creative way to get readers for your site Though granted, it might appear you actually read the post.
Now, the culprit could of course be, you are measuring 'visits' wrongly. Oftentimes 'hits' are confused for 'visits' and some log analyzers will simply fail to spot that multiple requests form a single visit.
So reducing requests (html,js,css,whatnot) will - ideally - vastly reduce the number of hits (a good thing: as in avoiding taking a hit). That doesn't mean you get fewer visitors. I'd check your log numbers to see whether you might have gotten more visitors, only serving them in fewer request/responses?