Jerome Gambit: Underground Openings or Gambits?

 

Like I said in the previous post, I was considering writing something on the topic of piece sacrifices on f7 - a dynamic in the Jerome Gambit (1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.Bxf7+) - when I came across another interesting, related, discussion, this time on StackExchange.

Are there any "underground" openings or gambits?

Playing a lot of blitz online, from time to time I meet quite strong players who regularly use very dubious lines that can have some shock or practical value in blitz or bullet chess, such as these, as White:

NN - NN

1.e4 e5 2.Bc4 Nf6 3.Bxf7+

Or, as Black:

NN - NN

1.e4 e5 2.Nf3 Bc5 3.Nxe5 Nc6

NN - NN

1. e4 e5 2. Nf3 d6 3. d4 Bg4 4. dxe5 d6

NN - NN

1. e4 d5 2. exd5 Qxd5 3. Nc3 Qe6+ 4. with Qg6 5. and an 6. early Nc6-b4 7. attack

I was wondering if all of this means that some players have their private analysis of some (objectively bad) lines for use in speed chess.

Are you aware of other similar lines? As you can see, I don't mean Grob's Gambit or Cochrane's Gambit, but the very bad lines...

The Halloween gambit maybe? – 

Glorfindel

Yes, I meant something like the Halloween. But perhaps even more unknown and unsound, as you can see from the samples... – 

1.c4 b5?! White often pre-moves the second move of Nc3 or g3 which just drops the c-pawn. – 

Ywapom

In bullet chess (1 min or less), you basically don't have time for thinking and will pre-move or make moves instantaneously often making assumptions about your opponent's moves. In such situation playing the best moves becomes less important; basically you just need to move fast without blundering too much. Playing chess at such short times becomes more about bluffing and less about thinking.

The practical value of dubious lines/moves can be two-fold: your opponent has to think (=losing valuable time) to refute the move your opponent plays a standard (pre-move) which is not the best in this situation

Due to the limited time it is difficult to refute such dubious lines even if you lose a minor piece. So there is little risk involved.

I doubt there is much private analysis involved. I also doubt there is much value in trying this at longer times (3 min or more).

There are tons of first 4 moves that involve ridiculously unsound sacrifices, but most of these usually involve Bxf7+ and have no place in opening theory.

These 'openings' are largely based on a gross overvaluation of castling rights: you can just slowly castle by hand, especially since the attacker usually has no other pieces developed yet (e.g. after 1.e4 e5 2.Bc4 Nf6 3.Bxf7+ Kxf7, the only developed piece is black's); if the defender loses, it's a result of being outplayed, and is no fault of the opening.

Therefore, such lines are hardly worth studying to defend against, and even worse to learn to use. Just fall back to basic principles (develop your pieces, do not play h6 without thinking it through...) when facing these, and you will emerge with a long-term advantage.

Sometimes there's some practical value in taking a line others feel is unplayable and making it somewhat playable. At best, you should be aiming for a line that gives the opponent lots of chances to go wrong but allows you drawing chances if the opponent plays perfectly. I could give ideas but your opponent could be reading this too. It's best to come up with your own ideas.

Some examples though: I recall Silman analyzing Damiano's defense and concluding that black's side was playable.

I remember years ago playing a Fried Liver as white on FICS. My opponent was undoubtedly using an engine. I lost and lost badly but that just goes to show what you can do if you analyze deeply enough.

I sometimes play the Englund gambit (1.d4, e5) as black. I can equalize about 99% of the time.

Yes, there are quite a few dubious lines one could try out when there is nothing much at stake. 1.d4 e5 2.dxe5 f6 comes to mind.

There was a book on blitz openings, but those variations are "fundamentally sound" according to the reviewer.