Why is typical move order for QGD among top grandmasters 1. d4 Nf6 2. c4 e6 3. Nf3 d5? Why does not black immediatelly go 1. ..d5? Also, why is QID via 3. ..b6 almost never played?
There is no real objective answer, both are playable at any level. Such variations in move order are decided primarily according to roughly 3 common criteria:
- a) Comfort zone of the player: which structures they're more familiar with, and therefore, they may opt for lines that maximise the liklihood of ending up in those.
- b) The types of variations and transpositions they want to prevent from occurring (depending on the opponent), which itself depends on various elements.
- c) The kind of game they've envisaged: double edged, conservative, etc. (this is a subcategory of b) essentially), all of which influence how committal you're going to be with your starting moves.
Therefore, these matters tend to be quite opinion-based, that said, here's an attempt to shed some light on a handful of key differences between the two specific lines:
More particularly for the line you ask about,
1.d4 Nf6 2.c4 e6 3.Nf3 d5 ... often called the anti-Nimzo qualifies as one of the most versatile options for black as there still remain a diverse set of variations for black to consider, to name a few (assuming
- On the solid side:
4...Be7[*] (leading to mainline QGD with
- Or sharper variations such as: the Vienna
Note that white is also keeping many options open with
3.Nf3 instead of
On the other hand, with
1...d5, well for starters, Nimzo Defence options are essentially ruled out, and assuming black is going to follow with
e6...Nf6, white is left with early options to divert towards fundamentally different structures such as the exchange variation of the QGD:
1.d4 d5 2.c4 e6 3.Nc3 Nf6 4.cxd5 exd5 5.Bg5 ..., compared to the move order with
1.d4 Nf6 2.c4 e6 3.Nf3 d5 where an attempt to transpose to an exchange variation with
4.cxd5 exd5 leads to poorer version of that system for white as the early
Nf3 is almost a lost tempo since black has to pressure
d5 (with early
f6-defender) while including an early
Qc2 to prevent black from creating a good light-square bishop with
So the whole setup with early
Nf3-cxd5 and without
Nc3 allows only for a nonthreatening transposition to the QGD exchange variations.
Instead, by not committing to
d5 [**] on the first move and playing
Nf6, black preserves the option of playing the Nimzo among other lines (and therefore, avoid QG's altogether if so desired), while transpositions to most variations with pawn on
d5 remain open, which leads us to the natural conclusion that: not making early committal pawn moves in the centre tends to leave us with more options on the table.
So as you see, all these lines are possible but the decisions are made according to one's preferences (and the circumstance at hand) and neither option (
1...Nf6...) is generally better or worse.
Regarding your last question,
Also, why is QID via 3. ..b6 almost never played?
it's not clear what you mean, the move
3...b6 is the defining move of the Queen's Indian Defense (QID), and it is frequently played (by e.g. Carlsen, Karjakin, Anand, Ivanchuk, ...).
[*]: This mainline followed by
6...c5 also happens to be what Carlsen - Caruana had prepared for during the recent world championship event, see e.g. game 7.
1...d5 also avoids certain lines that
1...Nf6 doesn't, but there's not enough time/space to get into that.
Both moves orders let Black reached a QGD guaranteed (if he wishes), but the move order with 1...Nf6 keeps White guessing. Until Black actually plays 3...d5 White has no idea if he's going to go for something like a Nimzo instead.
One possible reason to play 1...Nf6 first is to avoid the exchange variation of the QGD, which is considered a fairly good opening for white (40% white win rate and 43% draw rate in the database I'm currently looking at, compared to ~33% white win and 52% draw in the main line of the QGD for example).
[FEN ""] 1.d4 d5 2.c4 e6 3.Nc3 Nf6 4.cxd5
Of course, this is not to say that it's unplayable for the black end, but it's not considered black's best try for equality. Instead, by playing 1...Nf6 and 2...e6, black keeps his options open: if white plays 3.Nc3, black can most notably go for the Nimzo-Indian defense with 3...Bb4, which is considered to be relatively good for black and which many white players dislike playing against. When white instead plays 3.Nf3, then black can go into the QGD (if he so pleases) by playing 3...d5. At this point, any attempt at an exchange-type QGD (with 4.Nc3 followed by 5.cxd5) won't be nearly as good, as that early tempo that white has spent on Nf3 will make it substantially easier for black to consolidate his position, in particular to get his light-square bishop out while keeping his queenside pawn structure intact.
[FEN ""] 1.d4 Nf6 2.c4 e6 3.Nf3 d5 (3.Nc3 Bb4)
Of course, at the end of the day it all boils down to personal preference, especially since all of the mentioned variations are perfectly playable, even though top-level players might disdain some of them (due to the fact that top-level players operate on the smallest of edges).