Torturing its opponents to death by crucifixion was standard Roman practice. The details as imagined later hardly matter, surely? Is the fact seriously disputed?
I don't think anyone seriously disputes that crucifixion was a common method of torture and execution in the Roman period. Equally it's not in dispute that the details of the crucifixion as described by the RC Church stem, not from the first century, but from the Middle Ages, and that the 'traditional' idea that Jesus was nailed to the cross, and that he was speared in the side after only a short time, would both be departures from the normal Roman practice - the hands are not mechanically strong enough to support a person in this fashion for very long; metal nails were scarce and expensive; and the whole point of the excercise was to cause a long drawn-out death over many days. Expecting a crucified man to be dead after just a few days is a rookie error, and taking him down before the crows had consumed most of his flesh would rob the empire of their main objective - the provision of a grisly reminder to passers by not to fuck with the authorities.
The whole story smacks of an inexpert fiction written by someone who had heard of crucifixion, but didn't know the details.