Good/Bad f5-break in the Czech-Benoni

Hi everyone,

I am currently reading "How to play against 1.d4" by British IM Richard Palliser based on the Czech Benoni defense from Black's point of view, and even though the Czech Benoni is supposed to be an easy-to-learn defense without too much theory I have realized that actually there is a bunch of nuances such as the move order which makes a certain move good or bad depending on when you do it. This can be said of many openings but here (and in many other Indian defenses) where Black counters with a pawn lever such as f7-f5 or c7-c5 the timing is crucial.

This said I have been surprised a couple of times where Palliser mentions that the move is premature or bad, and then in another example in the exact same position (or slightly different but not relevant to the move in question) he says that the move is good. Let me show you an example:

In this example above Palliser mentions that f5 "is still premature". Now to the next position:

Here however he states that "Black can safely reply f5". I see no difference except an additional move from both players (White's Rb1 and Black's Kh8) which I do not think they have something to do with the move f7-f5 being discussed here.

Am I missing something here? Is there any expert out there on this opening that can explain the nuance of this move here? Why is it a bad move in the first example and a good move in the second one?

I am getting really confused and frustrated, and I am about to drop this defense because I do not really get to understand the logic behind this f7-f5 break.

Thanks a lot in advance.

Neat. I also see no difference in the positions. Perhaps if the second game had continued as the first Palliser would have commented f5 was bad. I always thought f5 was generally bad if White could occupy e4 with a knight after the break, but if Black could recapture with the pawn and keep the center f5 was generally good, like both of these examples. I will be interested too to see what stronger players think of these positions as I always this was a good way to fight as Black. Is White really much better in the first diagram after catpures and Nf6 or an immediate Nf6? ... if so, how about 14... exf4 with the idea of occupying the e5 square? Does that put too many holes in Black's position?

(I play the Czech Benoni but I play the "modern" lines (5... Nbd7-f8-g6-eventually eyeing f4) which are also covered in that book by a slightly different move order. The main reason to delay Be7 is to allow transpositions to the KID if White plays g3 or something.)

Yes, it is very weird. I cannot see any difference. Palliser mentions that black should not play exf4 unless he has enough control on e5, which means that if White has a knight on f3 or d3, then Black would lose control on that e5 square, and it seems that Black has a worse game after that.

Thanks for your comment.

I ran a deep position ananlysis with Houdini on the first "bad" position, and I'm not sure it's of any theoretical value because of lot of the moves seem silly and not to accomplish much. This could be because they're bad, shallow, computery moves with the engine not able to play well in the closed position, or because Black is already in trouble and can only "tread water." One such move is actually Kh8-g8. Houdini says 15... Rf7 (15... Nb6, 15... Qe8... I didn't make it look at my suggestions of 15... Nf6 or 15... fxg4 which I guess are probably bad) 16. g5 (seems odd to me to trap the Bishop out of play) 16... Qe8 17. Ne2 Bd8 18. b3 (why?) Nf8 19. h4 Kg8 20. Nd1 Rc7 21. a4 +over- 0.88/22 ... the King back to g8 can only be explained as getting out of the pin in the case of Qc3, and in some of the other options the engine wants to look at White does play Qc3 and Black is pinned. If I were to try to explain a lot of those moves, though I would be a loss, though. They're either odd-looking to me because they're so deep an nuanced I can't understand them, or they're actually bad because the computer has no plan yet in the closed position. Certainly by the end of the sequence White is getting ready to accomplish something, though, and Black has not improved his position. I can certainly run a version of the line with rook on a1 and the King on g8 and see if it's wildly different if you're interested, but I suspect the engine on its own here is not really finding the best "plans." Or, if it's the other thing, then having the "extra" move for Black not having to Kg8 doesn't seem like it'd help at all... perhaps with many extra moves Black could shuffle his pieces into a different, completely novel order, along the 8th rank.

Hi,

Thanks, that would be nice... if you can find any difference :/

IM Pfren has a good point. Indeed, in closed positions, such as one gets with the Czech Benoni, computers are notoriously unreliable.

Thanks, Pfren. I'm going to pass on running another engine analysis now as I think Pfren is right and I don't have the processor power to do anywhere near 50-ply (that last search took my machine about a day.)

I have tried to contact Palliser, but I cannot find his mail. I like Palliser's books but sometimes I have the feeling that he aims too high, i.e. in his books "Tango!" and "How to play agains 1.d4" (the one being discussed here on the Czech Benoni), where he is supposed to be explaining these openings in an easy way so that players new to them can start playing them with confidence.

However then you find things such as the one in my OP, where unless you are very highly rated or have a previous understanding on the opening you can be completely lost. The thing is that he ends the explanation there: "and Black can safely reply f5". That is all. Same position, different evaluations, nothing else. It is really frustrating.

I offer this recent loss where Black's f5 break was correct, but where the subsequent play was not.

Thanks for sharing.

Why is f5 suspect? If you're going to play it then you'll play it eventually right? When is a better time?