i think that over the two millenia that this happened, the cross has become romanticized as a symbol of the faith. to many Christians, this is a wake up call of how horrible a sacrifice Jesus actually made for all of the world. He despised the cross and the horrors of crucifiction, yet He looked passed it to what would be achieved by it. and according to people who have studied the history of the roman empire, if mel actually put everything that happened in the crucifiction, no one would be able to stomach it. so if anything, the license that mel took was a less-graphical one.