I tend to think it is more a case of denial rather than stupidity. These two adults have been keeping up a facade of normalcy for so long that I don't think they even know what normal is anymore! I have an 11 year old daughter that was just diagnosed with bipolar disorder and the worst thing a parent could ever do is deny and "fix" problems created by their child. Loving, gentle, parenting with an emphasis on consequence and consistency is key in the upbringing of a child with a mental disorder.
In my opinion Cindy and George know exactly what Casey did to Caylee, but their modis operandum since probably the begining of Casey's life has been to hide, fix, pacify and spoil any chance Casey had at being a productive person. Right now they are spinning their wheels trying to create a diversion in this hole pitiful masterpiece that their daughter has created. I have serious doubts that Cindy and George ever sought out proper treatment for their child with obvious emotional and mental disorders, instead enabled her to become what she is today. Casey and Casey alone murdered her child for no other reason than she was an inconvienence. In my opinion, she should spend an eternity...and then some behind bars. This coming from a mother of a child with a mental condition BECAUSE even though there is a diagnosis there, I STILL teach my child right from wrong and consequence for her actions while loving her with all my heart. Bipolar is not a defense, it is an excuse and a poor one at that.
I have to agree with you for the most part... but you can see in their faces on those videos where they visted Casey in jail... they do not believe a word she says. I was very surprised at Georges b.s. "our family is a hand, I'm the thumb...."
When Casey talks about "her family" Caylee is not part of it unless its an afterthought... "I just want us all to be together.. and Caylee too". That right there shows she isn't including her as part of the family, she wouldn't need seperate mention.
I held out hope for the longest time that they were babying her to make her feel comfortable enough to talk... but now I just think they are trying to convince themselves that there's a chance she didn't do the unthinkable.