What well known gambits are unsound?

Na5 f attacked c6

6. Qa4 is hardly ever played. More common is 6. Nbd2.

In chess.com's database Ng5 is never played, the only move out of 2 games is 0-0. Neither is that position reached in shredders database. Or chesstempo's. Even in chess365's big database including non-master games Ng5 is never played. I don't see how a line that is rarely if ever played could possibly be shown to refute an opening. It needs to be tested OTB before it can be claimed that the albin is unsound.

Black also has at least 2 other tries, 5... Nge7 and 5...Bg4. To claim the albin is unsound these need to be refuted as well.

Personally, I think the albin is dubious but not unsound, and it would take hundreds of pages of analysis to refute (if it is in fact refutable), not one puzzle.

shep because a move is rarely played does not mean it is a bad move.

This move was played vs a highly rated team of players-the top player of that team is now a correspondence grandmaster. This was a team match where the players of the

black pieces spent thousands of hours on this game. Because it does not happen to be listed on chess com means little.

the game was viewed internationally move by move for over a year.

Really, just because you have never seen a move or that a move is not published does not mean it is a bad move and in this case it is the best move.

By the way re your suggested move of 0-0 in this line--this team had played a master and the master used 0-0 [i believe] and the team demolished the master who played 0-0. So this was a challenge game as the team with

black had just demolished another good player.

My question is if it is the best move, then why does no one play it? And one game is not enough to prove that a move is good or bad, no matter who played it or how many hours they spent.

The medium team rating was 2283 with some very good players at the top.

The challenger at the time was rated 2538

There are lot of good moves that have not been discovered yet.

there were hundreds of years when no one played the sicilian defense but that did not mean that the sicilian defense was a bad opening.

I can assure you if a game is played at a very high level--someone who is interested in the best move rather than the most popular move with play that move.

The way to improve your chess is to be open to moves other than what you will see on vote chess or some other such medium.

Right now in another forum I am playing in a game where moved played scored very badly in chess explorer but it happens to be the best move.

As my very favorite song goes:

Won't you listen to reason?

Will you open your eyes?

It's a wonder what you'll find with an open mind

You may be surprised

yeah   

I know that one game played even at the highest level is not enough to prove any gambit is unsound--it is just an indication-maybe a good indication.

The best way to prove an opening is unsound is to use a engine on both sides and play it out.

But engines quite frequently have trouble with openings.

Use opening books!

Engines do have trouble with openings but at least having an engine play out a variation will give some indication.

Cannot use opening books for new ideas in an opening however. [by definition]

Of course a team of masters studying a game for over a year and using thousands of hours of analysis time--should give a very good indication-don't you think?

Regarding chess explorer and similar I have found that too many players tend just to choose the most popular move and also they seem to think it is the "best" move because it is popular.  To improve your chess you have to think better than that.

By the way, just for fun, I took the chess.com explorer and chose the most popular move each move--it was a sicilian--interesting variation and at the end WHITE WAS WINNING!!!! So I guess I have been WRONG all this time and chess is NOT A DRAW! White wins! 

It all depends on the level of play. In the WCC, playing the King's Gambit would be suicidal. However, at club level, it can rack in point after point.

I can't hold myself not putting this quote here

In the laboratory the gambits all test unfavorably, but the old rule wears well, that all gambits are sound over the board. - William Ewart Napier

For many years I was a gambit player and did well. But then I noticed I was doing well in spite of the gambits--not because of the gambits.

So then, I stopped playing gambits and my performance and play became much better...

I like where you're coming from, BigG. Some seem to have lost sight of the fact that this is a game and why we play games.

I used to play the Smith Morra so much that Ken Smith called me "my hero"

Fischer once said he believed the smith mora was good enough for a draw, but not more . He played it against Korchnoi once, and they drew .  

I was saying to BigG that I like his attitude. A 1900--2000 he's no slouch. You might beat him, but he'll enjoy the game. And at 2100--2200 unless you've written some well received books or something, you're not making a living at this. Might as well cool out and have some fun. However you define it.