The Cambrian Period marks an important point in the history of life on Earth; it is the time when most of the major groups of animals first appear in the fossil record. This event is sometimes called the "Cambrian Explosion," because of the relatively short time over which this diversity of forms appears. It was once thought that Cambrian rocks contained the first and oldest fossil animals, but these are now found in the earlier Ediacaran (Vendian) strata.
http://www.ucmp.berkeley.edu/cambrian/cambrian.php
Again, I think were having a dispute over our perceptions of time. I understand this didn't happen "overnight", 40 million years is a long time. But:
"Almost every metazoan phylum with hard parts, and many that lack hard parts, made its first appearance in the Cambrian. The only modern phylum with an adequate fossil record to appear after the Cambrian was the phylum Bryozoa, which is not known before the early Ordovician. A few mineralized animal fossils, including sponge spicules and probable worm tubes, are known from the Ediacaran Period immediately preceding the Cambrian. Some of the odd fossils of the biota from the Ediacaran may also have been animals representative of living phyla, although this remains a somewhat controversial topic. However, the Cambrian was nonetheless a time of great evolutionary innovation, with many major groups of organisms appearing within a span of only forty million years."
It was as some call "Lifes Big Bang" and considering the geological age of the Earth, 40 million years is very fast. It also fits into my greater point, which is not really about evolution at all, but the speed at which things happened. Such as this:
At 650 million years,Stars forming in galaxy J1148+5251; Make carbon, oxygen atoms and begin to blast these atoms into interstellar space
Just 220 million years after star formation,J1148+5251 has accumulated massive reservoir of cool molecular gas containing Carbon Monoxide (CO) molecules; Radio waves from these molecules begin their journey to Earth.
My point is how key events happened from the beginning until now, and considering the time frame, I think 220 million years is pretty damn fast to form a complete galaxy. Then we see the same thing with our Sun and the formation of the Earth. They are both 4.5 billion years old, so almost the instant you have a star begin forming, you have an Earth formed. In just 200 or so million years, there is already water present on the Earth. This suggests a fully formed atmosphere and magnetosphere in just 200 million years! The dinosaurs were on Earth almost as long.
Considering we are dealing with the Universe, I find it astonishing to see how things came together, the steps taken, and the quickness by which it was done.
EDIT: The above source actually goes on to say 13 million years:
When the fossil record is scrutinized closely, it turns out that the fastest growth in the number of major new animal groups took place during the as-yet-unnamed second and third stages (generally known as the Tommotian and Atdabanian stages) of the early Cambrian, a period of about 13 million years. In that time, the first undoubted fossil annelids, arthropods, brachiopods, echinoderms, molluscs, onychophorans, poriferans, and priapulids show up in rocks all over the world.
I'm going to take some time to read over everything you've posted so far, but I still think we are agreeing, we just are thinking of time in different ways.