[mvdgaag]

I think even an optimal strategy (in a game theoretical sense) for poker will have couter strategies that beat the optimal strategy.

Any strategy to be called a single strategy should be fixed. It can be 'raise 30%/fold 70% at random against a 20/15 opponent given this and that' so it is allowed to differentiate between a lot of variables that any person or computer could access. But within this information the strategy should be fixed.

In that case I think by definition the optimal strategy will be one that is least exploitable/most profitable against the entire range of possible strategies. But in that range are a few (probably themselves very exploitable strategies) that will beat an optimal strategy.