White: blue bird, Black: moonbus, notes by moonbus, initial ratings within 25 points.

This is so far a book line of the Semi-Slav. Generally, Black strives for the liberating move ...c5, while White strives to prevent this.

There was no point in retreating this bishop, as it was locked out by Black's own center pawns (all on white squares) anyway.

Strange move; I expected the knight to come here.

This cannot be ignored, exchanges are now forced. Exchanges open up Black's slightly cramped position and work in favour of equalizing.

This leads us into a potentially interesting endgame with 2 knights against 2 bishops.

I did not relish the prospect of leaving the queens on the board with two bishops bearing down on my king position after e3-e4.

Standard procedure calls for placing rooks on the c- and d-files. This unnatural-looking rook move is due to White's slightly awkward e3 pawn which hampers the natural development of the dark-squared bishop.

White effectively prevents Black's liberating move ...c5, and probably intends to double the rooks by playing Ra3-d3 at some point.

Black decides to liquidate the center, leave White with an isolani, and post a knight to d5.