■■■■ it 
i solved my recent problem by adding colorMatrix filter directly to each thumb (bitmap), which is inside a main movieclip (that also holds one other movieclip that acts as thumb stroke), and on that main moviclip i am adding a blur.
(so i dont need to re-apply colorMatrix everytime i want to add and remove a blur)
i apply the blur by activating the enter frame which calculates the blur on every object while it moves, and removing it by removing enter frame and clearing the filters array like so:
for(var i:int = 0; i < _mcArr.length; i++) {
_mcArr*.filters = [];
}
i am also applying alpha from 0 to 1 to each main movieclip when i apply the blur and reverse (from 1 to 0) when i remove blur.
now i discovered the problem, this clearing of filters array causes my thumbs (inside a main moviclips) to stay visible (alpha 1) at the end of animation.
you can see the main movieclip fading out but on the end of animation when that command happens (clearing of filters array, aka removing blur on the main movieclip) thumbs alpha jumps back to 1, and the main movieclip stays alpha 0.
wtf is that happening?
