static <A> void runStrategyWhileImprovement(Best<A> best, Steppable strategy, O... _) {
  double score = best.score();
  optPar int plateauLength = 1000;
  long sameScoreSince = 0;
  Double minRuntimeUnless100 = cast optPar minRuntimeUnless100(_); // run for this many seconds unless score = 100 %
  long start = sysNow();
  while licensed {
    if (strategy.step()) ret;
    ++sameScoreSince;
    if (best.score() != score) {
      print("Improvement after " + n2(sameScoreSince, "round") + ": " + callStringifier(optParam(_, 'printer), best));
      sameScoreSince = 0;
      score = best.score();
    } else if (sameScoreSince >= plateauLength &&
      (minRuntimeUnless100 == null || elapsedSeconds(start) >= minRuntimeUnless100)) ret;
  }
}

static <A> Best<A> runStrategyWhileImprovement(AIStrategy strategy, O... _) {
  runStrategyWhileImprovement(strategy.best, strategy, _);
  ret strategy.best;
}