on 01/17/11 at 20:35:34:
The "problem" is that Black has 2 theoretically respectable and more popular alternatives to 4...Be7. The 4...Bb4 and 4...dxe4 moves.
Anyone who plays 3.Nc3 against the French Defence has to be prepared for a range of lines by black. So black can play the Winawer,the Mccutcheon, The Burn variation, the Rubenstein variation or even Hecht-Reefsclager 3..Nc6.
So white players have a lot of work to do to prepare for the French Defence.
A useful rule of thumb for white is
If your opponent is higher rated
then play 1.e4 e6 2.d4 d5 3.Nc3 Nf6 4Bg5
4...Bb4 the Mccutcheon is unfashionable at high levels and black will not win if white plays well and knows the theory.
4...dxe again is very drawish.
4...Be7 5.Bg5 dxe is also drawish.
4...Be7 5.Bg5 Be7 6.e5 Nd7 h4 is the line that we are interested in. Black can draw if he knows how but attempts to win are risky.
If black is higher rated in my opinion he should play the Winawer 3..Bb4 or the Hecht-Reefsclager 3..Nc6.
If white is higher rated he should consider
1.e4 e6 2.d4 d5 3.Nc3 Nf6 4.e5 This is a main line where it is difficult for black to fully equalize but he should draw if he has a really good technique. If white is a stodge merchant this is the line to play.