I think it demonstrates quite a bit. All credible evidence shows the cloth is not from the First Century. There is no provenance for this Shroud from the First Century to the 14th. Therefore the visage is not of Jesus Christ. The Shroud is a valuable remnant of a funeral of someone in the Middle Ages.

What it demonstrates is how some people in the face of all logic and all evidence can cling to a belief which is false. No amount of data, facts, information can blast them away.

We can see it right here, right now. They can want it so much they believe it. The wish is the mother of the thought.