Zias and Hengel on crucifixion

On Paleojudaica, Jim Davila blogs this Reuters article:

Jewish remains give clues on crucifixion
By Megan Goldin

It focuses on the remains of Yehohanan Ben Hagkol and features comments from both Joe Zias and Martin Hengel. It's the first time I've seen comments from Hengel in the media on this topic in spite of the fact that he wrote the definitive book on the subject, Crucifixion in the Ancient World and the Folly of the Message of the Cross:

Professor Martin Hengel, a leading scholar of crucifixions from Tubingen University in Germany, said thousands of captured Jewish rebels were crucified by the Romans around Jerusalem during the first century, when Jesus lived . . . .

. . . . "It was used because it was so appalling. It was very painful and everybody could see the suffering. It must have been very humiliating too, hanging naked at the cross," Hengel said.

One of Joe Zias's comments raises a question in my mind:

Gibson's film shows Jesus being hammered to the cross through his hands, in line with the traditional view depicted in religious icons and paintings since the Middle Ages.

Zias said this reflects theology rather than reality. Jesus, like other victims of crucifixion, would either have had his hands tied to the cross, or been nailed through the wrist.

"You cannot crucify a person through the hands because there is nothing there but skin and muscle. It will tear. It has to be done through the wrists," Zias said.

I understand the anatomical point here, but if victims could be tied, might they not also have been nailed through the palms of the hands? Is the anatomical point the only one in favour of nailing through the wrists and if so, would not the possibility of victims being tied partly negate that? I wonder whether those filmic depictions of Jesus being nailed through the wrists (from The Day That Christ Died in 1980 onwards) are as much influenced by the Turin Shroud as by the anatomical evidence, not least given the fact that interest in the Shroud was intensifying in this period.

Update: Jim Davila comments on my comment in Paleojudaica.