Provention!: The Question That Cost a Young Capablanca a Game

https://www.youtube.com/watch?v=LH9hQGuShZY
Good day, chess world!

The first game in Capablanca's own Chess Fundamentals is a game he lost, that is exactly why it opens the book. Many chess masters will hide their defeats but Capablanca shows us all the value of analysing your loses.

Playing Black against Frank Marshall in their 1909 match, the young Capablanca stopped asking the one question that decides most games:
What is my opponent planning?

He drifted into a passive setup, missed a quiet bishop move he later admitted he simply never saw, and was slowly ground down by Marshall's queenside pressure.

The whole game is a study in prophylaxis.
I prefer to call it proactive prevention: before each move, ask what your opponent wants, then choose the move that takes it away and improves your own position at the same time. It is the habit even a genius can drop for a single game, and here it cost him the point.

I have built a free interactive lesson for this game on my website, with board diagrams and six rook-ending puzzles: https://chessexcellence.com/f/chess-prophylaxis-how-to-stop-your-opponents-plan-capablanca-marshall-1909.html
And two free note sets to go deeper: the Capablanca series PDF at https://docs.google.com/forms/d/e/1FAIpQLSfVtlFBDTaYahWI-VcpZOUIGn7ly5R4mYnjoEgg2OOgHn1tzQ/viewform and my Logical Chess study sheets at https://forms.gle/nEt1DWY5pKGq7T3n6

Four exercises from the game

Try to solve each before you watch. The answers are in the full game at the bottom, in the video, and in the website lesson above.
1. Black to play (move 8). Capablanca developed with 8...Nd7, but later recommended a more purposeful move that frees his light-squared bishop. What is it?

2. Black to play (move 12). Capablanca grabbed a queenside majority with 12...c5 and immediately doubted it. Which quieter pawn move keeps the structure healthy instead?

3. White to play (move 17). Capablanca admitted he never even saw this move coming. What did Marshall have ready?

4. White to play (move 25). Marshall finishes with a pretty stroke that made Capablanca resign. Find the combination, and the point behind it.

Play through the full game with my notes here:

Questions, or a move you would have played differently? Tell me in the comments. Good day, chess world.