Lecture has two parts, the material is quite mathematically intensive, however its a good introduction (and wake up call), to GTO strategy. The basic idea is somewhat simple, there is an ideal strategy (GTO = game theoretical optimum) in which your strategy cannot be exploited regardless of how villain responds. What is not talked about often in the media and commentator explanation of poker and poker strategy, is that given no other specific information, we should be striving to play a GTO strategy (whatever that might be).
GTO is difficult to define, as poker is a complex game, however certain specific situations are easier to define than others, and we can use those situations, in order to get a general understanding of what a GTO strategy might be in other more complex spots.
Often professionals with this knowledge are not running constant scenarios through their heads wondering what lines their opponents might take, but rather they are simply reverting to GTO strategy, and hoping to force their opponents to open up and make the mistakes themselves.
The idea of the video is if we get to the river and don`t like our GTO options, then we might re consider how we should play the turn, if the turn isn`t a favorable set up with respect to the hands we have available to us (because of our flop and preflop strategies), then we will revert to a flop analysis and so on.
I`ve watched these videos a few times, it was complete gibberish the first time, quite overwhelming, and basically disheartening...how ever after much study and consideration, this new understanding for the game has bred and new love for it...
Consider this topic as part of your study for the game, it is quite interesting and certainly the future of it:
https://www.youtube.com/watch?v=BuxCNZ0RVKA