Revision: What is Nash Equilibrium?

Nash Equilibrium 

• It is very important to know this during heads up SnG game. 
• ICM doesn't apply now since the tournament EV is now equal to chips EV. 
• Basically, it tells me when to shove or call unexploitably in a heads up situation. 
• Pushing and Calling Range  according to Nash Equilibrium

Unexploitable vs Optimal

• By playing unexploitably, it is a zero sum ( 0 EV) game assuming that everyone plays exactly according to Nash. 
• If any player deviates from the unexploitable range, he would be making -EV moves and the player playing according to Nash gains. 
• However, it is not optimal. For example, Nash recommends that shoving AA with 20BB+ is unexploitable. But this is not an optimal move though it is unexploitable. 

Playing Optimally

• In case of playing a player that we had no idea what is their push/fold range, playing according to Nash will ensure that we are not making too much of a mistake. 
• However, once we know the push/fold range of a player, we can then start adjusting our ranges as well. 
• For example, if a player calls a wider range than Nash suggested, we should tighten up and vice versa. 

Conclusion

Playing exactly according to Nash doesn't make us money in the long run. We should play according to Nash only if we had little information of the player. However, if we know the tendencies of the players, we should adjust/modify our game to increase our ROI%  in this game.