static L<Lisp> sortByArgumentHygiene(L<Lisp> l) {
  new IdentityHashMap<Lisp, Int> scores;
  for (Lisp x : l) {
    int score = 0;
    for (Lisp arg : x)
      if (arg.isLeaf() && hasRoundBracketHygiene(arg.unq()))
        ++score;
    scores.put(x, score);
  }
  ret sortByDescScore(l, scores);
}