Waitforseconds causing erratice flickering between active/not active objects

Hi I've written a script which on a Right-Click an Animatior activates and a caption appears. This toggles, so right-click again and the Animation reverses and the caption disappears.

The Animation takes about 2 seconds to compelte and I want to caption to appear after the Animation has finished, but then dissapear immediately on the second click.

I have the script below using a Coroutine to Waitforsecond (2) on SetActive(true). The activation works perfectly, there is a 2 second delay after the animation starts and the caption appears on time. But on the second right click, for SetActive(false), it just flickers erratically on and off for 2 seconds before dissapearing!

Do you know what's causing this flickering? I'm a compelte beginner to javascript so any help is really appreciated. Thankyou :)

 #pragma strict
 
 internal var animator : Animator;
 private var anno : GameObject;
 var clickCounter: int;
 var click : float;
 
 
 
 function Start () {
     clickCounter = 0;
     animator = GetComponent(Animator);
     anno = GameObject.Find("Caption1");
 }
 
 function Update () {
         Counter();
         Activation();
     }
 
 function FixedUpdate () {
         animator.SetFloat("Activate", click);
     }
 
 function Counter () {
     if(Input.GetMouseButtonDown(1))
     {
         if(clickCounter == 0)
         {
             clickCounter = 1;
         }
         else
         {
             clickCounter = 0;
         }
     }
 
 }
             
 function Activation () {
         if(clickCounter%2==0)
         {
              click = 0.0;
              anno.SetActive(false);
 
         }
         else
         {    
             click = 0.2;
             yield WaitForSeconds (2);
             anno.SetActive(true);
         }
     }