You are correct in that I was a bit too hasty so I revised it to a 3 star for the time being. It may block spam but I’m not going to risk the speed drop that I already noticed. I installed the plugin on a brand new server and ran speed tests before and after installing the plugin and once more after uninstalling the plugin. The server had no posts, no other plugins and literally just the default everything. The page loaded really quickly, then slowly (with the plugin enabled), and quickly again when the plugin was removed.
EDIT: Honestly, I’m not even sure what there is to troubleshoot because there’s nothing on the server at all other than a fresh install of WordPress and literally nothing else. With the plugin, it takes 2-3 seconds to load. Without the plugin, it loads in 199 ms.
EDIT 2: I made sure that my servers were both meeting the requirements as well. They are both on WordPress 4.4.2, PHP 5.6, and configured to allow the use of an .htaccess file.
