First, you should understand that the mode of death by crucifixion was not always due to blood loss alone, but more by the inability to breathe. When the hands are drawn outward and upward, it forces the muscles in the chest into the same configuration they would naturally go when you inhale, so in order to EXhale, it took a willful, forced “pushing down” on the chest to get the air out. If you hands are nailed, obviously each exhale causes the victim to pull hard against the solid nail with an open wound, causing extreme pain and further blood loss.
One type of cross known to have existed at the time of Christ was one that had a small block or horizontal board that acted like a crude “seat,” and it was designed to keep enough weight off the hands to keep them from pulling completely off the nails as could happen if the full body weight was on them. I don’t have a source, but I have read where experiments have been conducted using cadavers that demonstrate the bones of the hand are not strong enough to support full body weight on nails.
On such a cross, in order to exhale the person would have to put some weight on their nailed feet and lift their torso off the “seat” while simultaneously pulling on each arm and forcing their own exhale. If they didn’t have to move, even with nails through their extremities, the woulds would scab over and stop the flow of blood in minutes. By forcing the continuous agitation of the wounds, it keeps the wounds open and the blood flowing, increasing the shock to the body and eventually weakening the person to the point where they could no longer make those movements and succumb to anoxia.
No one is really sure of what kind of cross was used. It is entirely possible this type could have been used and the wounds could have been in the palms.
Wrist nailing is much trickier and could be counterproductive in a public execution meant to be extremely painful AND humiliating. Hit an artery and it could cause death in mere minutes. Hit nerve bundles and it causes such extreme pain the person would lose consciousness from the shock. Yes, I’m sure the Roman soldiers were proficient in their duties, but using a nail on a flexible, moving target does not produce surgical precision.
I’ve never read anything that makes a compelling case one way or the other, and as others have pointed out, it is not the anatomical precision that is the point of it all.