The Legitimate Cause of Jesus’ Death

Not by blood loss
Presuming Jesus was nailed to the cross, did blood oozing from the nail wounds cause his death?  The Roman method of execution by crucifixion was designed as a punishment to be prolonged in order to serve as a lesson to both the victim and all onlookers.  Since no vital organ would be pierced crucifixion usually caused a slow death.  If the victim expired within a short time he would deprive his executioners of satisfactorily meting out the sentence in accordance with their concept of justice.