That suggestion seems very reminiscent of the notion that optimally compressing wikipedia is the same problem as what generative LLMs are doing, by virtue of predicting the next letter/word/segment with high precision lets you compress it extremely well.
I think for chess you could get most of the benefit with a relatively naive engine; chessbase has a weak engine built in where you can hit space bar and it does a move which is incredibly useful since there's just one obvious move for a lot of positions anyway; if the move was especially tricky/nonobvious than it's also not what you would want when hitting spacebar to just predictably proceed anyway).
I think for chess you could get most of the benefit with a relatively naive engine; chessbase has a weak engine built in where you can hit space bar and it does a move which is incredibly useful since there's just one obvious move for a lot of positions anyway; if the move was especially tricky/nonobvious than it's also not what you would want when hitting spacebar to just predictably proceed anyway).