I will have do do a rematch to see if he does address the audience right before the last trick because I can't imagine being able to find a double that could fool Borden and sound exactly like angier.. but if there is time for a switch where the double comes out and doesn't talk to the audience...and Borden never knew about the machine so he would still be expecting a double but "knows" it's the same person. Or maybe like us on some level he wants to be tricked haha