I personally think that white has a good enough lead in development to compensate for the knight... But do they have a good enough one to win the game??
It is a very interesting opening. But interesting does not mean sound. No GM would ever dare play it as white. Not even at the master level. But below 1500, sure, why not?
It is a very interesting opening. But interesting does not mean sound. No GM would ever dare play it as white. Not even at the master level. But below 1500, sure, why not?
You are wrong, someone not only dared, but managed to win as well.
And this was not plain Muzio, but even wilder double Muzio:
You have a nice blog here:
http://blog.chess.com/Etienne/muzio-gambit-database
and another Muzio game:
British GM Raymond Keene used to play it at the GM level as well:
Thanks for the posts, @Narniacalls Actually it is a gambit that should be played more by higher ranked players.
Dragoljub Minic is another GM who plays it:
Wow so many amazing openings...
Nikolay Tsarenkov is an International Master who plays the Muzio at the master level as well.
7 Nc3 offering the second piece is a great line also, perhaps not as strong as e5, though worth a try.
>:)
You can find a collection of Muzio games here:
http://www.chessgames.com/perl/chesscollection?cid=1006233
and here is a well played defence, so people wouldnt think that white always have an upper hand 
I play the Muzio in bullet/blitz, and it's common for Black to be dazedly watching the train approaching but not knowing which way to turn to get off the track.
In GM annotations, the Muzio remains "unclear". Every now and then someone pulls out a prepared novelty when a win has big value, and they know that OTB their opponent hasn't the time to analyze fully. The King's Gambit isn't a settled issue, and I have found (and been victimized by) several refutations of GM analyses.
And to answer an original question, I would say that Muzio is dubious, it deserves "?!" mark in my book.
But, white scores surprisingly well with it.
365chess.com:
| 5. O-O | 54 |
|
chessgames.com:
| 5. O-O | 189 |
|
There is a reason why strong black players mostly prefer 4...Bg7 over 4...g4, it is just too risky.
So, I would say that if you know your lines, and if you like tactical game, I think that Muzio is nice try at live chess and OTB.
In online chess it is probably best to avoid Muzio (and especially double Muzio), as black can use the books to steer the game into lines where black is substantially better.
I think black is best..
What about 6. ... Qh4!
Yeah, Qh4 threatens nothing and it only puts the queen in an awkward place, it's hardly likely to be a useful move.
White answers Qh4 with d4, freeing the Q-side B, and Black is even further behind in development.
You need to study up on the Muzio Gambit to play it. If you don't know how to attack correctly after sacrificing the knight you will quickly be a piece down in the endgame.
The Muzio Gambit is very strong and gives white a slight advantage,
The reason modern day masters don't play it is because black is scared of the muzio and won't play g4!
I sure don't go into Muzio as Black any more on blitz time controls. The gambit is probably unsound but dangerous and you will be burning too much time on the clock while trying to find an adequate defense. If I had an opportunity to play against it in turn-based, I might try accepting. Anyway though the Black is fine with 4. ...Bg7
