I was using W3 Total Cache configured to use AWS as a CDN and in combination with Cloudflare, and 2 different customer support representatives from SiteGround told me that they do not work together, in fact, they told me that deactivating w3tc was a requirement to use Cloudflare.
I am actually making a very detailed analysis of the speed before and after w3tc deactivation and I am in shock. These are the results:
In Page Details:
a. Fully Loaded Time from 1.53s to 1.57s.
b. Total Page Size from 380KB to 480KB
c. Requests from 14 to 12
In Page Speed A92% to A96%:
a. 6 redirections disappeared taking “Minimize redirects” from D67% to A100%.
b. “Specify a character set early” went down from A100 to A99.
In YSlow B88% to A90%:
a. Use a Content Delivery Network CDN from B80% to A90%.
b. Reduce DNS lockups from A90% to A95%.
c. Avoid URL redirects from B80% to A100%.
In Waterfall:
a. Now the first operation is <https://www.howtohealemotionalpain.com/>; rel=shortlink which takes 1.04s to complete. Horrible!
In Timing:
a. TTFB from 364ms to 0.8s
b. First Paint from 0.6s to 1.2s
So, Cloudflare by itself does a pretty decent job without the need for w3tc to be present.
I wish that I knew how to get rid of that rel=shortlink that kills the timing so badly!