Looks like the suggested solution is to use https://googlefonts.3perf.com/ - which seems to rewrite the link tag to a script that does some DNS prefetching and forces FOUT to get a faster load time. Seems like too much of a stopgap.

If you really want to fully control the font experience, download the font package and CSS from https://google-webfonts-helper.herokuapp.com/ and host them yourself, on the same CDN as your JS and CSS. That way they'll load in parallel with your site's other assets and you have full control over all cache control headers as well.