*/
public int worth( TwoPlayerMove lastMove, ParameterArray weights ) {
int row = lastMove.getToRow();
int col = lastMove.getToCol();
GamePiece piece = board_.getPosition(row, col).getPiece();
assert piece != null :
"There must be a piece where the last move was played (" + row+", " + col + ")";
assert (lastMove.isPlayer1() == piece.isOwnedByPlayer1()) :
"The last move played must be for the same player found on the board.";
// look at every string that passes through this new move to see how the value is effected.
int diff;
diff = horzDifferencer.findValueDifference(row, col, weights);