Ok, the other day I was re-visiting this classic and I had my mind blown up by it. You see... I was watching the "One Dream" segment (which is really damn good, by the way) and I realized for the first time that the animators chose to have Becky casting her shadow over the surface of the lake while she was skipping on rocks across it... can you even do that? I mean, in real life, can you have your shadow being seen on the surface of any water body? It would seem to me that the light needed to produce the reflection of your being in the surface would be "eaten" by the shadow (thus, making reflection impossible).
I know I'm over-thinking this, but I have asked this to five people and no-one has come with an answer yet. My head freaking hurts xD