KC's friends have also been in that house, her brother's friends, family's friends, who knows who else? Duct tape or other items could have been removed from the home anytime before or after the murder, we don't know who else might have been in the home, or simply snatched items from KC's car along with Caylee, or from anyplace where KC had Caylee and also various items from her house. We have no idea.
There's no proof that KC had a motive, and we have no idea what predator could have gained access to Caylee. If more forensics had been done of the people Caylee had been around and locations, it would have helped rule people out and maybe discover an evidence trail somewhere.
To me the most incriminating thing is KC's bizarre failure to report the disappearance and inability to give information, yet, there are conceivable explanations for that. There are some subcultures where you don't rat someone out, you will be killed if you do or your child or family will. Or, there is the possibility that (rightly or wrongly) KC believed Caylee was safe with somebody. Or, that she was on drugs and couldn't remember what happened, or suffers from mental illness. etc
Personally, I haven't figured it out yet. Of course I can't rule KC out as perpetrator completely.
Bold me..
In the beginning thats exactly what I thought -- that she was so high she didn't even remember what she did with her own child. Ghastly!! I don't know what I think now. Still musing.