I'm guessing that the backspace character ('\u0008') simply moves the cursor position on character to the left and doesn't actually overwrite/erase the character at that position. The second line of code actually outputs another character that overwrites the 'C'
I think Richard is right. Please try this snippet. Notice where the cursor moves at the end of execution. If you can execute it step-by-step in an IDE, you can actually see the cursor move backwards :-)