1.e4 e6 2. c4

weak point is obviously the d4 square, but it forces black to change his plans quite drasticly.

any articles about this? opinions?

I think it's most likely to transpose to an Exchange French with c4, which is a fine choice if not the most theoretically critical. Are there any interesting independent lines?

I play the French a lot and have faced this only twice, long ago. Both times, I played 2...c5, transposing to a Sicilian. You're right, this is a change in plans, but the resulting position doesn't seem too complex to sort out during a game.

As far as I can see, it mostly does transpose to the Exchange, except the (strangely, quite popular) critical line of the Orthoschnapp Gambit: 2... d5 (most played) 3. cxd5 exd5 4. exd5 Nf6 5. Bb5+, where Black is believed to have a comp and usually regains the pawn quickly, as in 5... Nbd7 6. Nc3 Be7 7. Nf3 O-O 8. O-O Nb6 9. d4 Nbxd5.

To avoid it, White plays 3. exd5 Nf6 4. d4 for the Exchange.

i searched a bit in the chess database and think it will become my standard answer against french defence. lets see how that will work out.

i play as similar answer to caro-kann for what it is worth.

As someone who regularly plays the black end of the French Defense, I lick my chops when I see 2.c4, or any other sidelines such as 2.Nf3, the Wing Gambit, etc. Black equalizes easily with normal moves. For example 1.e4 e6 2.c4 d5 3.exd5 exd5 4.cxd5 Nf6 5.Nc3 Nxd5 6.Bc4 Nb6 7.Bb3 Be7 and here Houdini gives small negative numbers to Black, but the position is essentially even. There isn't even any surprise value in this line because Black's play is so easy and intuitive. Ironically, even though Black is *only* equalizing in lines such as this, or the exchange variation, I have an extremely high winning percentage with black, because, for some reason, White presses too hard and ends up losing. I'm honest and tell them this in the postmortem, but they don't listen, lol. I'm talking about players up to 2100. Nobody over 2100 has been foolish enough to play these openings against me. If you are scared of a much higher rated opponent and are trying to get a draw, perhaps then this could make sense, but even then I would frown on it as sooner or later you're going to have to learn the critical openings anyway. What better way than school of hard knocks.

I would suggest sticking to the main lines such as 2.d4 d5 3.Nc3 (3.Ne2) and getting knowledgeable in those lines.

I can't see why Black would want to gambit a pawn here with 3...Nf6, dxe6 ++/= (not 4.d4?)

I trust you meant 3.exd5 exd5 4.cxd5 Nf6. But here 5.d4?! Bb4+ =/+ as Black will quickly castle and put a rook on e8, as well as regain the pawn with a ready-made blockade on d5. The pony, in this one-trick-pony line is the timing of the d2-d4 move usually in an attempt to disrupt Black's blockade, similar to the idea in other IQP openings.

FYI, there is no space after the number in algebraic notation.

The last time I faced 2.c4, I responded with 2...e5. Even though black loses a tempo, White can't really transpose into any standard double-king pawn positions, since the pawn on c4 blocks in the king side bishop.