Nimzo-Indian Defense: Hübner, Rubinstein Variation
After 4.e3 against the Nimzo Indian, following Akiba Rubinstein's original idea with 5.Ne2 is possible - this is called the 'Rubinstein Variation'. White prepares to play a3 and recapture on c3 with the knight from e2, thus avoiding doubled pawns.
Pros:
- White avoids doubled pawns
- White may get the two bishops.
Cons:
- The knight on e2 impedes the Bf1
- White's development is slower
- Black can avoid giving up the two bishops