It's to do with the customary use of a headband to bind up the chin which means the chin leans forward into the chest, which makes it appear it has no neck and the separation of the frontal and dorsal figures.
I see. Your studies, then, did not comprise human anatomy and physiology. The issue has nothing to do with any
assertion of a "traditional" headband. The issue, as you would have seen had you read the thread (as it has been dealt with multiple times) is that the representation of the
frontalis is but a few finger-widths separated from the representation of the
occipitus, leaving insufficient room for a human
clavarium.
Try this: put the thumb of one hand on your own mental process. Spread your had up across your face, and mark where the tip of your little finger reaches. Next, put the thumb of one hand on the back of your neck, even with your jawbone. Spread your hand up and mark where, on the back of your head, the tip of your little finger falls. Now put the thumb of one hand on the spot you marked on the forehead, and reach to the spot you marked on the back of your head. In a normal human skull, that distance will be nearly the same as the other two distances. Now repeat the process with your chin on your chest. If tucking in your chin changes the
shape of your skull, I suggest you see a doctor.
The chin-on-chest-due-to-a-"traditional"-headband argument is nothing more than special pleading; it does not even address the actual problem of the absent calvarium.
The way the cloth drapes over the toes and shin explains the absence of feet on the frontal figure.
I see. You intend to answer questions no one asked, so that you might avoid the questions that were, in fact, asked. No "easy way out", there, at all...
There is also the Jospice imprint, a natural phenomenon which causes a dead body to form an imprint on a sheet, due to bodily fluids.
I cannot tell if this is carelessness, or equivocation. There is no "natural phenomenon" that "causes" a dead body to form a flat imprint on a "wound" sheet--there was one mattress cover on which it was claimed that this was "caused" to happen. Interesting that is appears to be so rare.
ETA The shroud is mentioned in the scriptures. See John 20:6 - 7.
"Then Simon Peter came, following him, and went into the tomb. He saw the linen cloths lying there, and the face cloth which had been on Jesus' head, not lying with the linen cloths but folded up in a place by itself."
The linen cloths (do note the plural) were
ὀθόνιον, "strips" (S/G3608) that were said to have been
δέω "wound" (S/G1210) around the body.
The CIQ fits neither of those descriptions.