“That seems almost perverse, that the dating scientists even picked the wrong place to get a piece. Someone who understood the shroud’s history ought to have guided them, and still even could.”
If you had a patched blanket, the patch was visible, and you were told not to collect your sample from the patch, I have every confidence that you could manage.
How is it possible that they could not? I don’t know what to think other than they deliberately collected their sample from the patch.
Even knowing that the patch work is there, it takes close looking with a photomicrograph to actually see the differences in the threads of the sampled area. The newer threads are dyed cotton to match the older original undyed linen flax threads. The newer threads have an "S" twist while the original Linen has a "Z" twist and are slightly larger than the newer threads. It is even more obvious comparing the threads under an electron microscope. The threads were not just interwoven, but the ends were twisted together in the "French Invisible Reweaving" technique with the idea the repair would be invisible to the naked eye. It was and is invisible.