anchor.diff:      var siblings = $A(thisArm.parentNode.getElementsByTagName("LI"))
   
       updateMoveControlVisibility('arm', thisArm.id.split('-')[1], thisArm, siblings)
  +    updateDeleteControlVisibility('arm', siblings);
   }
   
   function updateAllArmsControlVisibility(epochId) {
  -    $$('#epoch-' + epochId + '-arms li').each(updateArmControlVisibility)
  +    var armItems = $$('#epoch-' + epochId + '-arms li');
  +    armItems.each(updateArmControlVisibility)
   }
   
   function createStudyControls() {
  
positive.code:     }
      href += objectType + '=' + objectId
      var a = Builder.node("a", {
          className: objectType + '-control control',
          id: objectType + "-" + objectId + "-" + controlName,
          href: href
      })
  
negative.code:     var siblings = $$('div.epoch')
  
      updateMoveControlVisibility('epoch', thisEpoch.id.split('-')[1], thisEpoch, siblings)
      updateDeleteControlVisibility('epoch', siblings)
  }
  
  function updateAllEpochsControlVisibility() {
  