Is the danish gambit sound?

"... the Danish Gambit, 3 c3, perhaps deserves more respect than it usually receives. ..." - GM John Nunn (1999)

Of course, that was about two decades ago.

Does Anyone have a good video about the Danish Gambit

The two pawn sacrifice in the Smith Morra is well known as unsound.

The problem is black can play e6, which stops the very important pressure on the f7 pawn.

The Danish on the other hand is sound, but it's not a good try for an advantage, as black equalizes extremely easily if they know their stuff. However, at the more intermediate levels where nobody studies theory it's perfectly fine.

Example:

I found an interesting article on Danish Gambit : https://www.chessonly.com/danish-gambit/

The Danish Gambit is Aggro

Well, just look at the analysis. -0.5, -0.6 is basically Stockfish's way of saying that it's dead even but black can push for something.

i could beat you in a fist fight

I once played the Danish Gambit and lost the endgame because of lack of two pawns. Still my favorite gambit, though. I just did not take advantage of the Danish Gambit's good qualities.

I have gone over the Danish Gambit games in the 365 database pretty thoroughly, partly because I sometimes play the opening. Most of the recent master games are Danish Gambit declined. Of those that are accepted, the second pawn is usually declined. When the 2nd pawn is accepted, both pawns are usually given back with the exchange of queens with the Schlechter Defense. 

The gambit is fine if black tries to take and keep both pawns. The problem is that in master play, white doesn't get much of an edge when black doesn't try to take and keep 2 pawns.

The Goring Gambit seems better in general against good players and the Danish can often transpose to the Goring.

The thing is, you're down one or two pawns. But a material deficit doesn't always mean you're in a bad position. In fact in most variations it seems easier than usual to create dangerous threats because of the open files and diagonals you have. It's a matter of taste really, but at higher levels people are more likely to know how to defend properly.

I guess the book on that is that this gambit is advantage black, unless he doesn't know what to do with it.

I played around with your game in the analyzer, and it says black has an advantage until he played 7...Nxe4.  If black had played 7...c6 then (depending on white's play) black can take the knight on c3 with an eye towards playing d5.

There is a video "Crush Everyone with the Danish Gambit" with 600K views. It doesn't mention the Schlechter Defense 5...d5, which is clearly the most critical line after taking 2 pawns. The video seems dishonest,

The main line of the Schlechter Defense, leading to a queen exchange and even material.

I looked in the Masters Database, and 7 times black played 3...d5, 3 times ...dxc3, and once ... d3. The 3 times black took the first time, he did not take the second pawn. However, in the Big Database on 365, the Schlechter Defense 5 ... d5 is by far the most common line after 5.Bxb2.

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Imo, the Danish is just like other aggressive-from-the-get-go openings. Personally, I think it's great, but from what I've been reading, If your ELO is above 1700-1800 ish, then you're opponent can counter it with ease, and take the upper hand. If not, then it's a great opening! So I guess in theory the Danish is unsound and disadvantageous, but, lets be real, unless you're playing at a pretty high level, black probably wouldn't know all the opening theory. Hope this helped!

:tup