Is a bishop fienchetto a bad idea ?

Looking at stats of the Sicilian Dragon it seems to be. White wins are roughly 40 to 45% versus 30% for black (according to chess.com) even though the bishop bears down on the center squares.

The scope of the bishop may be a factor. The number of squares under pressure by a fienchetto is 9. If you have your bishop on c4 or f4 it's 11 and you have greater flexibility for tactics and trades in my opinion.

What do you think and am I wrong.

i think bishop fienchetto only helps if the center is kept open. if the center is closed,these fienchetto become useless. so a player must keep the center open to play fienchetto bishop. also fienchetto bishop often works well if it  points to side where the king has castled and the center is open.

now-a-days , almost everyone know this idea hence it is not good to fienchetto bishops in general.

EDIT: with due respect thrillerfan, i never said anything about king's indian defence. it looks like you are stuffing words in my posts . aslo i said that fienchetto bishop are useless IN GENERAL . inother words, these fienchetto bishops become passive if the center is closed.

a bishop is bad or good depends upon your understanding of the position.one more thing, i never said that bad bishop leads to bad position . my point is bad bishop becomes passive.

Clearly you don't understand the basis of what constitutes a good or bad piece.  It's not about the quanity of squares they cover.  You can't look at any one individual piece and base how good or bad the piece is standalone, and get an accurate reading of the situation at hand.

Chess is about coordinating all your pieces properly.  You might even have a bad bishop, but that bad bishop is what keeps the whole position intact where without it, possibly a critical pawn drops, and after that pawn drops, another drops, and another, and another, that was all covered in the form of a chain with the base of the chain being the initial pawn you lost.

You need to be reading books if you want to get better.  I would recommend the 9 books at the following site, starting specifically with the Orange ones:

http://www.qualitychess.co.uk/docs/14/artur_yusupovs_awardwinning_training_course/

WRONG!

So what you are saying is that because the King's Indian Defense involves fianchettoing a Bishop and the center becomes blocked, that the King's Indian is no longer played at the GM Level and is a bad defense?  You are delusional if you think that's a true statement!

Bad Bishops don't equate to bad positions.  The only time one can truly say that a Bad Bishop equates to a Bad Position is in an endgame when you have the scenario of Good Knight versus Bad Bishop, and nothing else but pawns and kings on the board.

A piece's activity is measured by the number of squares it controls : this idea is generally correct, and it takes away the need to use ideas like "bad bishop" and stuff like that.

Also, bishops inside a pawn chain can restrict the opponent's activity and protect your material (like a bishop protected a backwards pawn that is attacked by the rook. 

In response to Chessbond and the guy who responded to chessbond...

A very good way to work against a fianchettoed bishop is to clear all pieces out of the way (it's not common, but it can happen a good number of situations). Then the bishop became useless.

If all of your pieces have maximum scope in a closed position, I can only conclude that you must have a winning position. That is of course not the case. A piece that is not totally active can always restrict the opponent's play.

For example, a Bg7 that is blocked by e5 discourages f4, which is played a lot in the botvinnik structures to get kingside play but will open up the g bishop, making it very powerful. In the king's indian and the closed sicilian, the Bg2/g7 is also a good defender of the squares around the king that would normally be weak.

I recently played an otb classical game against Femi George, (1900+) in which this idea helped me to play a good opening and later win the game.

"A piece's activity is measured by the number of squares it controls : this idea is generally correct, and it takes away the need to use ideas like "bad bishop" and stuff like that."

It's not even generally correct.

More important is which squares it controls, otherwise there would be no benefit to getting a rook to the 7th/2nd rank, getting an advanced square for your knights etc.

This idea doesn't stand by itself, but it is usually correct.

To counter your arguments, A rook on the the 7th rank attacks the opponents pawns usually. This either ties down the opponent's pieces (rook needs to move into a passivity, or king is cut off on the back rank) or wins material (which can later be converted to piece activity:a passed pawn will tie down pieces ...become queen etc..). An advanced knight attacks squares in the opponent's camp, so high value pieces cannot move into those squares anymore, and it can reduce the opponent's activity.

The point of moving into the opponent's area is not just to increase your activity but to decrease opponent's.

It's a concrete game, statements about the number of squares a piece controls are meaningless.

I do know control of squares does matter and is very inportant ( refer to GM  Melik Krachiyan comments on Chess TV ). Also the comments I made were in reference to chess openings and nothing else. The coordination of pieces goes without saying.

I've watch a lot of chess commentary. I've never seen them count the number of squares a piece controls.

If you need it to judge the quality of a piece, go ahead.

I meant serious commentators though, not overpriced product spammers.

It's better than a rook fianchetto.