I'd be careful starting with this. C5 is much better. E5 is acceptable. C5 seems strange and I avoided playing it for the longest time. However, I've not found it be a very strong opening. The problem with D5 is that white has the tempo. He can play exd5, and lure your queen to the center of the board straight away. Then nc3 forcing you to move the queen again. Maybe e5+, which is answered with qe2. Too many traps white can set.

attacks d5, defends e4, develops a piece

? When I see a third pawn move before the minor pieces are developed I feel like something has gone horrible in the opening. c6 was the third pawn move and removes a development choice from the knight. It does give the queen some mobility. This is the fourth. None of blacks minor pieces are developed. If black must move a pawn, E5 would have been a far better choice. It still attacks the knight on b4-but with the dark squared bishop.

always watch the F pawn. That square is called the neck. It is the least defended square at the beginning of the game-and defended only by the king. Black must take the knight on E5 or he will at best lose his rook. If black fails to move the knight on D7, then bxf7 wins the game.

?? Black fails to consider where white might choose to move his bishop in response to his threat.