Here we go again!

This was a good opportunity to block the g-file with 24.g4.

Now Black is clearly better and his pieces cooperate wonderfully well.

Game over. Black won after some mutual inaccuracies, presumably in time trouble.

The basic ingredients of the Nievergelt Manoeuvres are already familiar, for instance from Stonewall-like structures.
In that case, however, ...g7-g5 immediately hits the doubled pawn on f4 and threatens to open the g-file. With the true Nievergelt Manoeuvre, you may hope to just create a half-open file in the long run. To refresh your memory - repetition is an important pillar of learning.

You won't have any problems at least considering the possibility of this move any more, I hope.

You see the difference. There's immediate concrete tension: Black threatens to take on f4.

White allows the f-flle to be opened without undoubting his f-pawns.

If White got in e4-e5 and f4-f5 he'd be in great shape. Now, however, it's Black who has the chance to sacrifice the exchange.