I don't believe in him but I doubt he would have used it.
If he really didn't want to get crucified then all he would have to do was to chop both his arms off.
They could still hang him though, but then would probably every christian be walking around with a rope around their neck right about now instead of a cross.
Better yet they could have decapitated Jesus, it would have been extremely funny to see a headless Jesus rise up from the dead and walk around in Jerusalem looking for his head, unable to speak he would be showing napkins where he had scribbled "I'm the messiah, have you seen my head?" to dead-scared bystanders.