Trompowsky: why does 1.d4 Nf6 2.Bg5 d5 3.e3 e6 score so highly for white in master games? I'm trying to find a suitable response to the Trompowsky using LiChess.  I saw the following line, which looks like it might transpose into more familiar QGD territory.

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1.d4 Nf6 2.Bg5 d5 3.e3 e6


On LiChess, in master games, white scores 52% wins, 33% draws, and 15% losses.  It seems black's moves are faulty for some reason.  I'm not sure why though---it looks like white has a sharp line.

For contrast, after 3...c5 white scores 24% wins, 48% draws, and 29% losses.  So 3...e6 scores significantly worse.

Question: Why does 1.d4 Nf6 2.Bg5 d5 3.e3 e6 score so highly for white in master games?
3..e6 closes the way for your light-squared bishop, but I don't think that's too good of a reason to reach such scores (I checked on ChessTempo and got similar numbers)

Please be careful about possible bias due to player strength differences. A move may score worse simply because it is often used as a "drawish weapon" against a stronger player. This is the case of the French exchange variation, where Black scores better in a symmetrical position! But there could be other reasons why an opening system is more common among weaker players

I would tend towards an explanation of this kind, since there does not seem to be a clear "refutation" in the position you show (4.c4, 4.Nd2, 4.c3 and 4.Nf3 all score similarly.

Please specify your own skill level for further advice on how to build a repertoire around these lines to be possible