Removing Event Listeners - Are they needed all the time

Question

My goal is to increase the performance of my project so I would like to know if it is always a good idea to remove event listeners. More specifically, lets say I have a movie with severals scenes and several frames within those scenes. Each one of the frames has an event listener:
Example:
Scene 1
Frame 1 (EventListener)
Frame 2 (EventListener)
Frame 3 (EventListener)
Frame 4 (EventListener)
Scene 2
Frame 1 (EventListener)
Frame 2 (EventListener)
Frame 3 (EventListener)
Frame 4 (EventListener)
Questions:
Does Flash continue to listen for an event in Scene 1/Frame 1 when the playhead has moved to Scene 1/ Frame 2?
Or does Flash just listen for the events when the playhead is in a particular frame only?
Should I remove the event listener once I leave a particular frame (should there be remove event listeners on each frame)?

Answer 1

Just mentioning, the addEventListener comes with a parameter you can set to true or false called a weak reference. On desktop flash apps it can become time consuming to constantly remove listeners, especially when things drop off the display list frame to frame. You can mark them for automatic garbage collection by using the weak reference property.
e.g.
Credits_bnt.addEventListener(MouseEvent.CLICK, goCredits, false, 0, true); // set weak reference to true (e.g. remove when no references exist anymore automatically)
Eventually garbage collection will remove that reference automatically when there's nothing left on the display list or in memory to use it.
However, if this is targeted at mobile, you absolutely want to remove the reference as soon as possible when it's not needed for memory conservation. On a desktop it's not that big of a deal.