For those who don't know it, it's a line in the English Opening where black replies 1. c4 with d5. Why is there almost no theory about this defense out there? Some books mention 1. c4 d5 but don't explore the lines further, claiming only that it's bad for black after 2. cxd5. However, my coach prepared this line for me because i don't like facing the English, and it usually transposes to lines similar to Scandinavian (after 2. cxd5) or Queen's Gambit (after 2. d4 or other), which i'm comfortable with. We have studied the main lines a lot, and didn't find any refutation for white which makes the defense unplayable. What's your opinion about this defense?

I've played a few OTB and online games from this position, and it looks ok for black. English players usually try to play natural English moves when i play this defense, reaching the structure above, which looks comfortable for me. I think it's hard to immediately exploit the fact that white still has both center pawns. Maybe with optimal play by white.

It's not the top choice but it's more or less as "bad" as Scandinavian.

I dunno about this one. I play the Jaenisch every now and then, but not in a must win situation, starting 1. c4 b5. You might try it. A lot of players aren't sure how to face it

Here is a gambit I made about the Anglo-Scandinavian Defense:

if u like to play queen's gambit declined as black (but maybe u accept it or play something else like Albin...), just 1...e6 and d5.

The idea is to take with a pawn in centre.

1.c4 d5? 2.cxd5 Qxd5 3.Nc3 is very poor for black.

In scandinavian, u trade d5 vs e4, a central pawn, while here only c4, this only favors white. And u lose tempi with your queen.

A coach advocating this is a very bad coach, go and pick another one.

8 ... bxb4

Strong players are telling you it is a bad defense and they are telling you why it is a bad defense. Listen to them [and also get a better coach]