public int evaluatePieceDevelopment() {
    int score = 0;

    int[] minorPiecePositions = new int[]{ 1, 2, 5, 6 };
    int turn = isWhiteTurn() ? 0 : 112;

    for ( int pos : minorPiecePositions ) {
      if ( !squareEmpty( pos + turn ) && !hasPieceMoved( pieceAt( pos + turn ) ) ) {
        if ( isWhiteTurn() ) {
          score -= 50;
        } else {
          score += 50;
        }
      }
    }

    return isWhiteTurn() ? score : -score;
  }