For me this video is less about watching what the opponent is doing and more about using the solver to investigate range construction: meaning showing how he's using the solver to in this example to make decisions about constructing the flop cbetting/checking range in order to achieve the right frequencies. He walks through how he is using the solver to explore EV between different combos to guide his range construction away from the table. Sure, we know that we want to cbet generally at X% frequency, but how do we go about selecting the right combos when building that cbetting range? He walks through identifying combos to add using EV differences and simplifying strategies using the concept of EV regret, arguing both that simplification aids in allowing a human to use/implement a strategy correctly (versus being unable to implement a very complex strategy) and that some of the solvers complexity (e.g. raising pot 2%) comes from the need to be balanced in a sim when both player's strategies are perfectly known - this level of balance isnt necessary in the real game, again arguing that simplification poses little risk and using EV to simplify.