> Read access still consumes resources - you may want to read up on what "denial of service" means and check your outrage. CloudFlare sits between you and the host server, and it's their responsibility to cut off DoS attacks before it can affect the host server. Their heuristics may not be perfect but it's not exactly a simple problem to solve.

It's hardly rocket science to determine when a DoS attack is occurring based on the overall traffic level. And until it is there is no need for countermeasures.