So what we (at least I) know is that:
1. It was written in the house, using Ramseys' pad and sharpie
2. It took at least 30minutes to write it (more probably an hour)
3. Manner of addressing and tone change
4. Phrases used can be associated with several popular movies
5. It's the longest RN till this day
6. It's the only RN that was found in the same location as the body of the victim, location being victim's home from which the victim was supposed to be kidnapped.
This was never supposed to be a true ransom note - it's too long, it was written at the scene of a crime using with what was found in the house, it starts with presenting themselves as foreign faction then gets all personal with JR, there is not one of their causes or more plausible requests listed (like release from prison of their mates etc.).
Whoever wrote it, did this after JonBenet was murdered, with clear intent to falsly present what happened as a planned kidnapping.
If the kidnapping was the original plan then the RN would have been written beforehand, which means not in the house, using Ramseys' stuff.
The length - if it indeed was a ransom note, it would not be almost 3 pages long. It makes no sense whatsoever if its original purpose is to be a genuine note asking for ransom.
The only way someone who was a kidnapper would write such a long note is if they knew that they had enough time to write it. There is no way that an intruder, whether waiting for the Ramseys in the house while they were away or slipping into when they went to bed would take that much time to write it. Even if the intruder was alone, waiting for them to come back, they would not know when the Ramseys would be back and would risk to be discovered.
Movie references do not mean that the person who wrote RN did see all of those movies or was a fan of them. DH was by then a classic and shown on TV enough times to be a part of pop culture so one could be familiar with the expressions without having actually seen it.
At the beginning it starts with Mr Ramsey and has is pretty distant tone but then that changes and gets personal. Foreign faction is mentioned but after a couple of lines it is clear that there's nothing political to it, there's no mention of their cause, nothing.
Sorry for the long post. I wanted to share my view of RN considering what most makes sense, and contrary, what doesn't. Of course, that does not mean it's not possible at all that a real kidnapper wrote it but I think the chances for that are extremely low. This was never ment to be a real ransom note.
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