The conclusions are not “ad hoc" and founded on analysis of the under oath testimonies of those present. Your inability to rebut the testimonies is duly noted. JohnM reposted the image with the title “Oswald's sack" and when asked about the person who took the photo (and when) failed to reply.
I find the notion that Oswald would construct a bag to transport the rifle, find that in order for the rifle to fit disassembled it, then simply leave the open end unsealed during transport, laughable.
I didn’t see anything that required rebuttal. Unless I missed it, Mytton hasn’t responded to this thread at all since he posted the first one. This is unusual, I hope he is just busy and is okay.
This is definitely my own conjecture:
Going from memory, Ruth Paine has said that she doesn’t remember seeing the rifle in the belongings she transported to her house from New Orleans. And that she suspects the rifle could have been in the duffel bag. That makes sense to me. LHO could have disassembled it (so that less of it would stick out of the top of the duffel bag) and further concealed it in the blanket before he packed it into the duffel bag. At some point the disassembled rifle (in the blanket) was removed from the duffel bag and placed on the floor of the Paine’s garage. If this theory is true, then LHO should have had a pretty good idea of how long to make the paper bag in order to conceal the disassembled rifle while transporting it into the TSBD.
Sealing both ends of the paper bag is your idea. It just doesn’t make sense to me that it was necessary or desirable.