Can someone explain why the dock is translucent?

The rest of the translucent overlays/menus make sense, if the logic is to "create a sense of dimension", as stated on the iOS site.

But it makes no sense for the dock to be translucent. It's on the same plane as the other icons.





Keep it simple. Just keep the page indicator as separation between movable and static icons, with no background effect, and voila.

.