I recall an excellent article by Tom Purser when Kf2 was claimed to be the winning opening's move - or maybe not completely ?! In any case. I also tried it in a fast game and guess what - Kf2 did win.
De Bouver - Dardha ( 2014, Antwerpen )
1.d4 Nf6 2.f3 d5 3.e4 dxe4 4.Nc3 Bf5 5.g4 Bg6 6.g5 Nd5 7.Ne4 e6 8.Ne2
Varying from both Diemer's 8.c4 as played in Diemer - Kopp ( 1947 ) and the proper continuation 8.h4.
8...Nc6 9.c4 (diagram)
Picking up Diemer's suggestion, one move later. Will my opponnet take the bait ?
Yes he does ! And now comes the move...
Black now should have played 10...Nb6, with a small black advantage. But baffled by my unexpetced move, black makes a mistake,
Blocking the retreat of the bishop
And white has a small advantage which lead to a white win.
Check out Tom Purser's post on this, including the link to the Tim Krabbé article - it is really great reading.