The Hennig Schara is a variation of the Tarrasch Queen's Gambit and we get to it after the moves,
1.d4 d5 2.c4 e6 3.Nc3 c5 4.cxd5 cxd4 [4..exd5 is the 'normal' move]
In this position, white can take on d4 and still have 2 defenders of d5, which means that white is winning a pawn if they want to. The open position, and swift and easy development give black plenty of chances to fight for an initiative and an advantage.
So a typical sequence might be 5.Qxd4 Nc6 6.Qd1 exd5 7.Qxd5 [Winning a pawn] 7..Bd7
Black avoids a queen exchange and develops another piece off the back rank. Often, black will castle queen side in this opening, and launch a huge attack on the king side. Black intends to develop with gain of tempo by Nf6 hitting the queen and then Bc5 hitting f2. The most common move here is 8.Nf3, but in a recent game from the Untergrombach Open played 5/1/15 white played the novelty 8.Be3, putting his bishop in front of a central pawn.
It's an ugly sort of move at first glance, but when I thought about it, Be3 prevents black's favoured development of the dark squared bishop to c5, blocks the c-file, develops a piece, and doesn't exactly hinder the f1 bishop which will probably develop to g2. In the game Cofman (2162)-Bongatz (2141) there followed a fairly natural sequence, 8..Nf6 [winning time developing and attacking the queen] 9.Qd2 Bb4
Developing the dark squared bishop to pin white's knight seems a reasonable developing move and brings about the position above. Black has a mighty lead in development, but is a pawn down. It's a very interesting position to work out if white can safely untangle and remain a pawn ahead, or whether black's activity is worth more than a pawn. As an exercise, I think it would be good to play loads of games from this type of position for both black and white to try to better understand the requirements of the position. White is solid but awkward with a pawn plus, black has all the play but has to justify being a pawn down.
This poition reminds me of a line I've been playing against the Evans Gambit, the StoneWare variation 1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.b4 Bxb4 5.c3 Bd6
Black accepts the pawn, places his bishop on an ugly square where it protects e5 and asks the question of white, what exactly have you got for your pawn?
And then, of course, there is the Bd3 retreat in the main line of the Two Knights Defence where white retreats a bishop to an ugly square to control a vital central spot. 1.e4 e5 2.Nf3 Nc6 3.Bc4 Nf6 4.Ng5 d5 5.exd5 Na5 6.Bb5+ c6 7.dxc6 bxc6 8.Bd3
These types of positions are becoming a part of modern chess, and as much as we old classical players blanch at the thought of playing such an anti-positional move as placing a bishop in front of a central pawn, if there is a specific reason for doing so, then we should judge the move on its own merit, not on the general principal.
Saying that, I think if I came up against 8.Be3 in the Hennig Schara, I'd be a happy black player. The game in the Hennig Schara continued with 10.a3, which I'm not sure is the best move in the position. Black traded on c3 which may also not be best. 10..Qa5, 10..Ne4, and even 10..Ba5 may all come into consideration, and the thought of this position is giving me the urge to dig Stockfish out to analyse the positions. In the meantime, here's the game which was a real long battle, ending in a pawnless rook versus knight ending.