Chess School Quiz Challenge #6

Challenge
Christopher Noe is slightly better, no question. His doubled rooks dominate the only open file but can't capitalize on it yet. As nice as it looks, the black position is actually suffering from a problem. What is it? And how did Noe solve it?
Solution
"Talk to your pieces", advises US grandmaster and author Yasser Seirawan to his chess students. Seirawan explains that pieces in distress will come forward and give us hints on what to do. We just have to talk to them.
With his memorable advice, Seirawan addresses one of the most important concepts in chess, one that comes into play in almost every game: improving pieces.
Improving pieces is what chess players do when there is nothing concrete to do. Then we make sure that each of our pieces plays along and is positioned for maximum effect.
Christopher Noe spoke to his pieces in his duel against super talent Leonardo Costa in the German Masters 2023, which had gone well so far. While the rooks looked happy, the knight on g6 spoke up. "Help me, Christopher," said the knight. And complained about a lack of flexibility.
As it stands, the proud knight is tied to a task of a lesser nature. It covers the e5-pawn, otherwise it does nothing. The knight can't move, then the pawn would be lost. But the knight would like to move in order to look for outposts near the center instead of standing on the kingside with no prospect of moving forward.
When the knight told him his problem, Noe didn't have to think long: 22...f7-f6. That stabilizes the central pawn and makes the knight flexible. In the following moves it happily whinnied its way to e6 via f8. Suddenly the horse standing on the sidelines had become the cavalry of a centrally mobilized army.