I would state it differently. "Assuming the description of what took place was as accurate as eye witnesses typically are..." There are claims that Jesus studied mysticism in India where he could have learned the technique of slowing his heart rate to near zero. Indeed, there are also claims that he taught the technique to Lazarus (his brother-in-law?) in order to perform a "miracle" (bringing Lazarus back from the dead). Since he "died" overly quickly on the cross, it is not out of the realm of possibility that he went into his trance and fooled the soldiers watching him. Just a thought.