It is a very nice article that I'll study in detail. In practice, if you can do this while playing, it is probably better than pure randomization versus all but the super-sophisticated opponents (or GTO robots).
However, and this should be made clear, utilizing card removal effects (CFR for Calldown Frequencies River) is an exploitative measure, it is not GTO. There is an (actually explicit in the article) assumption that the bluffer will bluff more or less according to the blockers you hold, and not according to the size of his bet relative to the pot size (though the bluffer is actually unaware of this, he might think he is playing GTO).
It is seemingly so that CFR is GTO since the bluff catching range has ha fixed size on a given board that is the correct GTO size. But this is an illusion, since there are hands outside the bluff-catching range stronger (versus every range in the world) than certain hands within it. What's really going on is that we aren't really playing GTO by assuming the opponent is bluffing too much/too little according to the hands we hold.
There is a way that the bluffer could counter an opponent playing CFR. He could use his wrist watch to determine when to bluff. Sooner or later the CFR player will make a bad call with A2 and a bad fold with A8 (from an example in the article where A2 is a call but A8o is a fold). It is probably possible (in theory) to go further. (The bluffer could consider his blockers to the callers blockers and adjust his bluffing frequency accordingly. This is just a silly mind game, but it illustrates that every deviation from GTO can be exploited.)
Having said that, the article and method described therein is excellent, and much more stimulating to the human mind than true GTO, and it probably works better versus humans (that don't use their wrist watch to randomize bluffs:)). CFR is close enough to GTO and probably deviates from it in the right way.
