I think that perhaps an easy way to do this would be to place the "before" graphic over the "after" graphic and just have the slider control the "before" image alpha. Here's a good example of how that works: http://www.flashandmath.com/howtos/sliderstepper/
What you've just said is one of the most insanely idiotic things I have ever heard. At no point in your rambling, incoherent response were you even close to anything that could be considered a rational thought. Everyone in this room is now dumber for having listened to it. I award you no points, and may God have mercy on your soul.