Color me skeptical. Consider that if David's winning percentage is 63.6, being weaker is actually an advantage, and Goliath's optimal strategy is to abandon most of your resources in order to become the new weakling. That doesn't make a lot of sense.

I'd really like to see Toft's criteria for including wars, for deciding the winner, and for deciding whether David was using the optimal strategy. The only unbiased way to do this would be to have the categorization done by a third party who had no idea what the object of the experiment was. For best results, by several people working independently. And did he include all the hundreds of little wars between the US and various Native American tribes?

Or did he just take some famous wars (probably famous precisely because they were very close or had surprising results), call the ones where the smaller side did really well "David using an unconventional strategy", and then proclaim an unusual number of victories?

Even if the experiment was done correctly, asymmetric conflicts in wars can't really be generalized. Often it's something like "Big country tries to colonize little country", in which case little country is fighting on its own ground and just needs to make big country annoyed enough to go away. There's a big difference between that and basketball.

Speaking of basketball, in a lot of games there are successful but unstable strategies. Imagine a game where there are strategies 1-99, where each strategy is more likely to win, but also takes an increasing level of expertise. Imagine also that Strategy 5 has a special property - it beats any strategy numbered in the 90s, but no other. Imagine also that it takes some training investment to use a strategy - you can't just switch strategy numbers willy-nilly.

Matches between masters of this game will tend to look like 98 vs. 95 or something. A beginner may step in, use Strategy 5, and win a few games against masters who were expecting him to also be a master. But eventually the masters will switch to Strategy 89, and massacre the beginner. After all annoying beginners have been eliminated, the masters will go back to fighting among themselves at the 90s level. I can't think of a good example now, but I remember exactly this sort of thing happening in a few sports.

I wonder if the full-court press might be equivalent to strategy 5 here - something that other basketball teams could defeat, if they put in a bit of extra training, but since everyone knows that no one uses it no one trains to defeat it.

One last thing: I think my post Help, Help, I'm Being Oppressed is relevant here. The article plays a kind of dirty trick to get our sympathy on David's side: it says that the Goliaths are trying to alter the rules to form a cartel to prevent David's brilliant but unconventional strategies from allowing him to compete on a level playing field. Because that's how overprotective that evil Goliath is of his advantages and power.

But imagine the situation was reversed. David, through sheer pluck and spunk, was managing to win in the traditional way, and Goliath used a dirty trick generally considered to be against the rules, like using his vast monetary resources to hire a computer scientist to design an unbeatable fleet by AI. We would immediately scream "foul!" and be outraged that David's shot at the prize was being taken away so unfairly.

So we need to make sure we're uncoupling the question of whether we're rooting for David or Goliath, from the question of whether it's okay to win using dirty tricks that violate the spirit of a game and potentially make it less fun for everyone else.

I worry about selection effects - maybe underdogs only choose unconventional strategies when they could think of one that seemed promising.

One interesting pattern in there, that the article doesn't draw into a conclusion - the two main examples presented, Eurisko and the basketball team, both were faced down by unofficial officials who tried to get them to conform and lose - and they backed down.

I would have gone for the kill. Let them cancel the tournament, let the ref foul the game. Ultimately, being too conciliatory cost them the war.

Taking the broader view, I wonder how much complaining about cheats is really an attempt by Goliath to have slings declared unfair. And how much of the desire to be nice and conform is evolution telling David to fall in line.