Queen's Indian Defense

I am trying to learn about the Queen's Indian Defense. One of the popular lines goes as follows:

1. d4 Nf6 2. c4 e6 3. Nf3 b6 4. g3 Ba6 5. b3 Bb4+ 6. Bd2 Be7 etc.

My question is about black's fifth move, Bb4+. If black plans on moving the bishop back to e7 on the next move anyway, why doesn't black just play 5. ...Be7? Does black obtain a better game with white's bishop on d2 than with white's bishop on b2?

I think the point is to either saddle White with moving the Bishop to d2 (as opposed to b2 or the N to that square) or moving the N there and binding him up until the pin is eliminated.  (And Black has Ne4 to further trouble white.)  Other alternative moves for Black after 6. Bd2 are just taking the B or Qe7 -- though, according to chessgames.com, Be7 does the best at thwarting white.  I'd pick up a book -- Emms' Starting out the QID is pretty good (I own, but have not read it yet) and Soltis' book is also a pretty good starting point-- PM me for a copy of that one.

I don't think I answered your question, but hopefully I've lead you towards other resources. 

On that note, what is the (dare I say "real") answer to Groucho's question?

ZV

Thanks, ZeroVector. Does anyone else have any ideas about this?

I think white wants to put the bishop on b2 in QID and if black forces white to defend Bb4+ with Bd2 then bishop is "misplaced" and it will take time to move it back to b2.

Aha, here is what it says in "Understanding Chess Openings":

- "The point is that after b3, the natural square for White's bishop would have been b2. Later, perhaps, White will try to put this bishop on the long diagonal all the same, but on c3 it is less securely placed that on b2 and also deprives the knight of its natual development square. On the other hand if White brings his knight out to c3, he will still have to remove his bishop from d2. So it turns out taht Black's manoevre doesn't lose a tempo after all." - GM Arthur Yusupov.