hunl

Heads up poker is precisely about equilibrium. Your straddle reference is also irrelevant, this is not live multiway poker.

"Tricking an opponent into thinking it has metaphorically thrown rock" extrapolated into a poker example would be betting larger/smaller, calling more/less, folding more/less than is optimal in a given scenario in the hope that your opponent makes a (bigger) mistake. You're simply hoping he makes more errors than you, the AI instead choses to just make zero mistakes and let the opponents do the rest. You can see this in action for yourself in Heads up limit holdem by playing Cepheus (http://poker-play.srv.ualberta.ca)

If you define a 'not very good' strategy as losing at a maximum of 0, then sure. Playing optimally means the worst case scenario against any opponent would be breaking even. It doesn't have to be trained on individual playing styles, it is simply playing each spot theoretically correctly.

An example, say the humans are getting to a river situation with too many bluffs for a given betsize, an exploit for the AI would be to always call. The opposite is also true, if they are bluffing too little it should always fold. The players notice that the AI has adjusted, and adjust their frequencies - now exploiting the AI. By taking an exploitative approach the AI leaves itself open to be exploited, this is not the goal.

If this were rock paper scissors, the AI is doing the equivalent of always throwing each at 1/3 - even when it's opponent throws rock every time. It could switch to paper, but a thinking opponent will now switch to scissors, this will continue until we are back at equilibrium. The AI aims to play poker in this same fashion, having the correct frequencies of actions for a given range in every spot.

You can't lead it to believe a point is an optimum, it's just responded to a bet size/check in isolation given the information it has. If you 'feign weakness' in a given spot it will just respond as optimally as possible to the bet size.

For example attempting to feign weakness by betting small in a spot where your entire range should bet large is not tricking the AI, it's just passing up on EV for the players, good players are not going to play poorly in hope of tricking the bot for future mythical EV gain.

Also, there is no 'colluding' in heads up poker.

The aim of the AI isn't to adopt to poor strategies, rather to play an approximate optimal strategy itself. It's aiming to be unexploitable, the further the other players deviate from optimal, the more it wins. It's EV (expected value) comes from the other players not playing optimally, it doesn't care about exploiting individual weaknesses.