Double Fianchetto - Good/Bad

recently alekseev (2710) lost to an unrated player against the double fianchetto in a rapid game:

Here is one of my game where my opponent played double fianchetto and I crushed him.

uhm using fianchetto in my sicilian dragon variation but im keep losing when i use that oppening :(

if you are going to play a setup like that you just have to know what you are dealing with.

As others have said, the double fianchetto setup can be sort of "slow" in that it takes 2 moves to develop each bishop. In the meantime your opponent my get a lead in development and also a strong center. So if you like to chip away at a strong center than the df setup may suit you.

if you look at the kasp=korch game above, you see that Korchnoi did play in the center to get open lines etc BEFORE he commited to the 2nd fianchetto. If you just mechanically go into the 2 fianchettos regardless of what he opponents do, you are just giving the opponent a free hand to setup whatever center he wants to setup

Out of the 3 advantages/disadvantages in  chess (time, space and material) the double fianchetto in my opinion involves "time".  It  takes 2 tempii to make a move that actually seeks to control the center (central squares d4,d5,e4,e5). 

However, it has been demonstrated that when the B reflects off the edge of the board onto a new diagonal it actually  gains  a tempo in certain positions.  In other words the B's starting position is on a square at the edge of the board.  When  it moves into the fianchetto square at b2,b7,g2,g7 it is very probable that it gains a tempo in certain positions.  A tempo gain that the opponent is not even aware of.

If you would like to know where the  tempo gain has been demonstrated or simply would like to know more please let me know.

double fianchetto often makes sense as a part of a setup (Reti, some lines of Modern Defence where white plays a4), but as the first four moves it does not exert enough pressure. You need more pressure on the opponent center, like a pawn exchange that has already taken place, or a permanent threat thereof) to make it work. Also there are some enemy pawn structures that render it less than ideal. I often start the game with 1.Nf3, 2, g3 etc. If opponent goes ...d5 and ...c6, I am happy with double fianchetto or with early e2-e4. If opponent goes ...d5 and ...c5, it's either e4 (KIA) or d4 (Tarrasch), but not double fianchetto.

i think, while symetry between opponents' sides is known to be "drawish," symetry in one's own camp tends to be bad, or at least very temporary.  but i know one gm who likes the double fianchetto, so what do i know?

hard to time your pawn breaks and not get squashed. hard to even choose which pawn break works. never liked openings with no long-term prospects.

First of all, you can be very speedy in taking up all the space on the board and gaining lots of material, but when the opponent is left with just one good queen and knight/bishop, there can be checkmate. Chess is more about positions and mating strategies than the other rationalizations.

Secondly, while the fianchetto takes two tempi it does gain control over 6 squares all the way to the backrank. A knight gets 4 in one tempo (hence the adagio 'knights before bishops') and a pawn just 2. Reason enough why most top players use it.

Fabiano Caruana has used the double fianchetto as well with success. It works when people study the lines before playing it. It can be tricky since especially on the queenside involves severe weaknesses if not defended well. So next to the offensive power, one has to consider the defense strategy as well. Engine analysis validates the double fianchetto as playable in many openings.

By the way the opening the original poster showed is impossible - and ridiculous; you can simply take, everything is undefended. I would call it the McDonalds Opening. You just want to be out of the situation as soon as possible.

I am currently trying it in the Pterodactyl both in Sicilian Dragon and Modern Defense. I like to call it the Dimorphodon Variation. Here white decides to counter with a double fianchetto as well (maybe call it the Double Dimorphodon). Whether the knights go to the flank or the center, and when to take in the center can decide the entire game. Some nice tactics too, like beefeaters.
Engine shows that there are playable lines.

Perhaps the English Opening (like many-a user already suggested) as White would be your cup of tea. To be precise, the English opening and the Réti Opening have a shared line where both bishops are (intended to be) fianchettoed:

Please can i get the pgn

as a VERY general rule. the more center pawns cemented in the middle of the board your opponent has the less viable the double fianchetto is.
in a system like a double english where center pawns are delayed it is customary to double flank. Agaisnt a two pawn center ,esp if the knights are developed on f6/c6 and its mirror, it works just fine. agaisnt 3 or even 4 pawns in the center it is usually dubious

lol

Nowdays the solution with 4....d4 is considered as good as any in meeting the english for black. White can end up playing a temp up modern benoni position but objectively that opening is so bad a tempo more doesn't give an advantage, especially if use it to create a bad bishop with b3 and Bb2. Black also doesn't have to play c5. It is even a possibility for black when white doesn't play b3 https://www.chessgames.com/perl/chessgame?gid=2135792

I like it, It has it places but I wouldn’t force the double fianchetto as it’s not always the best strategy, with that said, I use it in the Katalimov, KID, English and Reti depending on my opponents set-up because I prefer playing for long term strategies and imbalance positions.

I generally believe the "double fianchetto" setup is positionally flawed. In a few variations, this is playable, but as a guideline, I would avoid this as it seems like your two Bishops are competing. I actually made a video on this "Double Fianchetto" setup and why I believe it is positionally flawed. It isn't a topic I see come up a lot, so lucky for you I made a video on this

I'll also post the game example I referenced in that video via my second video: