Yannick Clément writes by email:
Just like it is a historical fact that the Romans used various positions for crucifixion, it is also a historical fact that they used various types of things at the end of their flagrum. In the case of the Shroud man, the most important thing to note concerning his scourge marks is the fact that, beside a Roman flagrum, there is no other ancient type of whip (coming from Antiquity or Medieval time) that could have leave those types of dumbbell shape marks on almost every parts of his body… If someone can show me a whip that was used during Antiquity or Medieval time in Europe or outside the Roman empire during Antiquity that also had something round at the end of the leather tongues (like a metal ball or an animal bone), I would consider the scourge marks evidence differently. But so far, I have not come across anything of that nature to change my mind…