Must Use Plugins ... "are plugins installed in a special directory inside the content folder and which are automatically enabled on all sites in the installation. Must-use plugins do not show in the default list of plugins on the Plugins page of wp-admin – although they do appear in a special Must-Use section – and cannot be disabled except by removing the plugin file from the must-use directory, which is found in wp-content/mu-plugins by default."

The current scripts are really only there to minimise the default chattiness of WordPress a bit if a project doesn't need that openness. Apart from that, the scripts do not promise any special kind of security. Test them sufficiently before using in your own project.