OddOneOut,
There was perhaps a reason for the size’s 12 if you were 9 going on 10. Maybe he didn’t want anybody to know he had changed JB upon first glance, so he chose the Wednesday pair. Also, like I said he very possibly could have seen Mom wrapping them while they were both in the basement. So he knew where they were and what wrapping paper.
More then likely the pair of underwear had to be gotten rid of because they contained JB’s blood as well as the pink pajama bottoms. We have discussed this here before and came to the conclusion that perhaps these items were carried out by Patsy’s sister in her sweep of the house via Jonbenet’s American girl doll. Remember the cotton stuffing found in the wine cellar? It could have been removed from the doll and the doll removed from the home. No dogs were called into this crime scene, obviously.
There is no evidence of an Intruder. This was a SA coverup case. There was no Foreign Faction.