In what universe Lightspeed is a HEALING cooldown? It doesn't do anything to your healing output, since it doesn't affect your GCD, only your cast time. If you're trying to use it to top a tank, you're gonna fail every time. It's a skill that allows you to have more breathing room to weave your off GCD skills, just like the Enhanced Benefic trait. Your comments only show how you failed to understand the job in its most basic aspects.