Blundering is a sin

From "Adam made imperfect choice in opting to commit his sin" in the South Florida Sun-Sentinel:

Q. Considering that a truly perfect chess player would be incapable of making a bad move, and likewise a truly perfect singer would be incapable of hitting a sour note, then how could a truly perfect man such as Adam be capable of committing sin? That Adam chose to disobey God indicates a character flaw in his design.

A. Unfortunately, it is your hypothesis that is flawed. There has been no such thing as a perfect anything since the fall of Adam and Eve. With sin came imperfection. Even the best chess player cannot perform 100 percent of the time at 100 percent accuracy.

So whenever I play badly apparently I have Adam to blame. Now, how does one become a born-again chess player?