You are depending on the claims of the people who would be next on the suspect list if she did leave Caylee behind, so obviously their testimoney cannot be relied on.
Caylee's body was found in the vicinity of the home, all the items found with the body came from the home. The implication is that Caylee never left the home and likely died there. So, if people are saying that Casey left with Caylee, and they also happen to be the next people on the suspect list, don't you think that perhaps they might not be truthful?
Then you have to look at Caseys behaviour after she left. She behaved like someone who believed that her child was safe with the grandparents. If that is not the case, then, according to the scenario you have laid out, we would have to believe that she is some sort of deranged psychopath that was the model of a loving mother, then, spontaneously and for no reason, killed her daughter as she was driving off and behaved like nothing happened, when it would have been much simpler to just leave the kid with the grandparents. Moreover, you would have to believe that in the absence of any evidence to corroborate that.
I don't believe all that for one moment. I believe that she left her child in the care of the grandparents, something happened, and the stuff afterwards was the family circling the wagons to protect one of their own, and that one was NOT Casey.
There is actually nothing at all connecting Casey to Caylee's death other than the ever changing accounts of her parents.
This is the red letter item for me. It is what convinces me that Casey is not responsible for Caylee's death, there is a far more likely explanation of what happened that fits the known facts. Most of the people I know who followed the trial (who are not WSers btw) have similar questions. That is why the jury acquited her.
If you think about it, and are honest with yourself, that explanation makes the family's behaviour before and after the trial make a whole lot more sense.
The issue with Casey is that people have this romantic idea about motherhood and what they expect in terms of behaviour. But in real life people often do not behave like that. Casey is without question one of those people. That, coupled with (in my opinion) an attempt to help cover what actually happened, is what got her into trouble. And once the image as a child killer has grasped the public mind, feuled by conviction in the media, it is incredibly hard to let that go. Once that happened a trial with the direst of consequences became inevitable, no politician would dare resist that, even once it became clear that the evidence simply was not there.
I remember seeing lawyers on CNN (Toobin I think, who is a former prosecutor) thinking that the case was overcharged. You can see their comments on the video clip
here.