While I understand the frustration that your internet is causing you, putting the cooldown on deactivation instead of activation basically makes using CS easy mode. The point of having the activation CD is to make healers be strategic in when/where they decide to do damage. If the CD is placed on deactivation, you never have to worry about that. Oops, I popped Cleric right before a tank buster? NBD, I can now instantly remove CS and heal/shield him.