Question: Delétang's Triangle method

Deletang's Triangle mate net looks like this,

Second net(White king is in somewhere out of the net)

Third net(White's knight is in somewhere out of the net)

But to make the second net from the first net, the knight should go to e5 to restrict black's king to go g4.

But after Nd3 or Nd7, Black king can go toward the bishop or the hill and can wander the center for a whole endgame. Well winning side can play W Manoeuvre, but that usually takes more than 30 moves. Also, it does not have any theory of making basic position of Bishop Knight mate, so we cannot sure that W manoevure as plan B of Triangle Method always works.

-W manueovre

Actual question: I am wondering there is any theory of Delétang's Triangle. And how many moves does it take?
Between W manueovre & Deletang, which one is easier and less-risky theory?
 
(I know that this checkmate pattern is so rare and difficult to mate even Grandmasters fail, but I just don't want to end a winning endgame a draw. I will wait.)

Different people will have different opinions. I find the W method simpler with the initial task of driving the opposing king into the "wrong color" corner with your king on c3/f3/c6/f6 .