Stockfish

When you start seeing big gaps in where you think the evaluation is and where Stockfish thinks it is, that's when you start spotting your weaknesses.

It looks like masters rarely play it in the database but Stockfish approves of the move.

I've been restructuring how I study my repertoire using Stockfish to go through my lines and specifically flag spots (in a notebook) where the eval swings hard within a few moves

4. e4 seems good, maybe a little better. I don't think you need a book or course for either if you study this with Stockfish.

Even if you lose one time, a little analysis with Stockfish open should prepare you for next time.

Stockish thinks black's best might be to sacrifice the knight with bxa3 (the white knight is eventually forced back to a1 to stop the pawn, but that's just a long, slow untangle away from a win).

the best move by stockfish with the intention in most games to go 0-0-0.

I haven't seen that many instances of someone claiming to have found a solution and then confessed to having used an engine after being inquired, but rather stuff like "I've put this through Stockfish and it says..." I think a comment with the correct solution is more helpful to people reading it than saying the first wrong variation I could think of.

Parent context: I had 2 engines play it against each other. Black wins easily. Reply: Thanks for your comment bro. I had stockfish play it against itself. You were right about the rook coming to c2, but also the king coming to b3. A key part I didn't appreciate was black always pushing the h/g pawns to provoke some sort of weakness.