I pretty much agree with this, except color or pattern of clothing can help mask a certain amount of movement. I hike just about every day. So I'm in the presence of deer every day, and elk periodically in the winter/spring {alas, they aren't this low during hunting season...} and if I am wearing white on snow, or my Flecktarn camo, I am certain movement in the brush is masked to some degree. Critters will take notice, but not immediately flee. In solid colors, I believe the entire outline of movement is seen and "registered" in the mind of the animal, and the respond accordingly.

The actual color of the camo I am not certain matters, but the pattern does I think. Some wear orange camo and say it works well. Problem I have with the current popular "hunter orange" common in the States now, is that it is so flourescent I really believe it must be highly visible to animals. I have little experience with it.