Nothingness - I'm interested on how you keep track of the pieces in the notes - as it is now, every time your opponent moves a piece, you have to update the position - so lets say a pieces was at A1, and they just moved it - you have to update the position of that piece. (If it was labled someway, you would never have to update the piece location.)
... but that is why I'm asking how you do it - maybe I'm missing an easier way.