code: function (progress, adv) {
    if (progress) {
      var id = progress[0]
        , pos = progress[1]
        , insertM = this.findMatch(id);
  
      if (!insertM) {
        throw new Error('tournament corrupt: ' + id + ' not found!');
      }
  
      insertM.p[pos] = adv;
      if (insertM.p[(pos + 1) % 2] === WO) {
        insertM.m = (pos) ? [0, 1] : [1, 0]; // set WO map scores
        return insertM.id; // this id was won by adv on WO, inform
      }
    }
  }
docs: given a direction (one of the above two), move an 'advancer' to that location