One possibility is that the fiber is there due to transfer or environmental. Pretty much any RDI 'explanation' for DNA could be used to explain fiber, Patty "hugged" JB with the sweater and jacket, and so it was on JB's person. Then a hypothetical IDI would transfer such stray fibers onto a sticky surface like tape
You know, we could actually sort of test out these ideas.
We ask group of volunteer young 6 year old blond wf who match JB in intelligence and psychology, with their parents full knowledge and consent.
We then ask them to meet them after bedtime, after everyone is fallen asleep, and see what % does so, or leave the door unlocked. We could vary the experiment by having them dress up as Santa claus or in plain clothes.
Let's suppose hypothetically speaking a group of child psychologists have an actor tell a 6 y/o wf that Santa is coming, and leave door unlocked or meet them after everyone has gone to sleep for a special visit and secret gift.
let's suppose out of "representative sample" of 6 y/o wf, 20, 19 comply. Then the likelihood JB might have done this is pretty good. If only 1/20 or 0 comply then the likelihood is pretty not so good.
I don't have preconceived notions of how most wf 6 y/o's would respond, and whether their response would differ based on closeness, dress, Santa clauss appearance, date of the year, etc. We could even vary using blacks, hispanics, boys, children of gay couples, poor children, low or high iq, christian or atheist, etc.
Of course this would beg the question of why this sort of thing doesn't happen more often? My reply is most people aren't child-killers. Now that I think about this, if this research were published, and showed most 6 y/o wf would leave a door unlocked for a "friend" they trust, I'm not sure that's such a good thing. If this is what research shows, then it kidnapping by some teenager where $118k is a lot of money, might be more plausible.
That's sort of the same objection I have about Burke -- if he were to wake up and saw what his parents were doing, how would they have responded? How could they be *sure*, short of death, that he would not tattle on them. Unless, of course, BDI.