Would Christians catch on to someone trying to dupe them like this (details follow)?

Say there was somebody that was really persecuting Christians and trying to wipe them out, then saw that he could take advantage of them instead. If he claimed to have had a vision and faked going blind from it, then pretend to be healed through faith, would Christians believe him when he tried to say he had been chosen to tell them more about Jesus and God than they had ever known before? What if he claimed all this happened on the road to Damascus?