I have Cloudflare CDN enabled on my site, and up until a few weeks ago, my cached content was being displayed properly through the CDN (meaning, the WP comments were at the bottom of each file). For the past couple of weeks, I've noticed that the cached pages are not being served through my browser (multiple browsers, logged in and not logged in). I finally have had some time to troubleshoot a little bit this afternoon, and have found that when I have Cloudflare enabled, it never seems to pull the WP Fastest Cache page. It pulls the non cached page. If I disable Cloudflare, I then see the WP Fastest Cache cached page. I purged the cache on Cloudflare, then enabled Cloudlfare again, and sure enough, it shows the non cached page again. If I disable it, then the cached page with your comments shows up. I know this was working a few weeks ago, so I am not sure which update caused the problem. I hope I've given you enough detail.