What? No, it’s definitely not a problem. If I include all the different weights of a font family in my CSS, but on some pages don’t use the bold weight, for example, how is that a problem? The browser only downloads the fonts that are actually used for exactly this reason.
What I mean is that the CSS should be minified to remove _any_ extraneous rules, and should be done automatically, just as it's done with most compiled binaries.
If you're using those font styles later on, but still using the same stylesheet, that's obviously alright, the performance-testing tool would need to be updated in order to spider through all the pages to verify where each one is being used.
