If it was just as good for white any attacking player like kasparov would play that every time since the point of the king's gambit is to attack. But it's not as popular anymore because there are known defenses for black that are quite good. I think it's pushing it to say it's just as good theoretically as the ruy lopez. I think the accepted lines lead to some advantage for black even if some people consider them equal. Some of it is a matter of taste I guess. I have learned the king's gambit for black and I'm relatively comfortable against it and hopefully that extra pawn will be worth something. But also black can choose many safe lines like 3...d5 which equalizes so black can get either an equal or preferable game. He must learn 3...g5 for an advantage but 3...d5 along with many others giving back material have no problems for black. But king's gambit lovers are too close minded and claim it wins by force instead. Maybe against an unprepared player, but it shouldn't be something to fear since it can be learned, and white has to know all of black's lines while black not too many. By technically unsound I meant inferior.
How NOT to respond to the King's Gambit!
the king's gambit is technically unsound, not that it loses but white is supposed to be at a slight disadvantage instead of the traditional slight advantage. The most important thing for black is to know and understand at least most of the theory. That's how you combat all dangerous openings. If you know very little about it, unless you're very strong you will have a very dangerous game and it's very likely you'll fall into a trap by just playing a natural move. Moves like these also lead to wild games in themselves, so even if you've been following the theory there is still some room for error.
Not true. It leads to equality to quickly for many top GM's who would like the pressure of the queens gambit.
It is as sound as the Ruy Lopez, and just as good for white.
my 4 mil mostly master db gives, since 1970, both players 2500+
Ruy lopez games = 10,320
King's Gambit games = 185
I think if GMs thought the KG was comparable to the Ruy Lopez, they'd play it a comparable amount... certainly more than they do. At the elite level there appears to be no comparision between the two.
As for the rest of us, I think we're free to play whatever suits us! 
I'm rated about 1500 and I love playing the kings gambit! Even though in theory it isn't the best opening and black can gain a slight advantage this requires very precise play. If grandmasters have lost to this opening then it is plenty good enough! I spent a while learning and using the opening and its very useful seeing as nearly no one knows the proper defenses and I've had alot of quick wins using it.
What should this player do once they cross the 2000 threshold? Should they play the KG and/or the Ruy Lopez? Should they cross back to the Ruy? Should they take the KG out for a spin and see just how high they can get with it?
Clearly the LAST thing that you want to do is to have such a narrow repertoire that you would like to change to something else but can't because your playing strength in other openings is 400 pts lower.
That is a problem I thought the KG had. If it's fine at the lower level, if you happen to become 2000+, you pretty much have to abandon your repertoire because your position will just not be very good against the superior players, so time has to be taken to learn it. But if you learn the ruy lopez for 5 years, you won't need nearly as much effort there since you're much more familiar with it.
Maybe it's as simple as using more against lower rated players, but still using it occasionally against higher-rated players. If you become known as "the KG guy" then maybe it's not so good, but I'm sure a lot of value will remain in the opening if it is an occasional weapon.
Maybe it's as simple as using more against lower rated players, but still using it occasionally against higher-rated players. If you become known as "the KG guy" then maybe it's not so good, but I'm sure a lot of value will remain in the opening if it is an occasional weapon.
Yeah, that's what I've been saying this whole time. it should be used as a suprise weapon because if the other guy knows you play the KG, then he can just book up on the theory. Personally I wouldn't want to play at a disadvantage with white no matter what, because no matter how well you play, a good result is not certain since you're worse. But I do think gambits teach players about attack, I just don't think in OTB it's the most reliable choice because it would be better to get that for free. You say how people make mistakes well, they could make a mistake in a safe position and then you can get the initiative for no price. That happens at lower levels just as much! Honestly, I think the KG is maybe one of the best weapons in blitz. However, to play blitz is to ignore most parts of this huge game in hope of an attack, which seems rather shallow. So to win in blitz is not so huge.
Here's another good example of a recent live game of mine, how NOT to respond to the king's gambit:
@tarius78 - After black played 5...f6 then you can play 6. Nxg5. Black's f6 move exposes the king on the e8-h5 diagonal. After 6. Nxg5 you threaten 7. Qh5+.
So, tarius - did you ever play against JG27pyth? I'd like to see how that game went.
honestly, I can't remember - let me check my past games and see, if not, I think I'll challenge him!! then post it, regardless the result, I promise :)
the king's gambit is technically unsound, not that it loses but white is supposed to be at a slight disadvantage instead of the traditional slight advantage. The most important thing for black is to know and understand at least most of the theory. That's how you combat all dangerous openings. If you know very little about it, unless you're very strong you will have a very dangerous game and it's very likely you'll fall into a trap by just playing a natural move. Moves like these also lead to wild games in themselves, so even if you've been following the theory there is still some room for error.
Not true. It leads to equality to quickly for many top GM's who would like the pressure of the queens gambit.
It is as sound as the Ruy Lopez, and just as good for white.