Apart from which it works! Yes, sorry. Loss of concentration. I saw your solution afterwards, Rd7. Very nice.

b7 Qc6
Rd6 Qxd6
b8=Q

I am less confident of this though, and feel it isn’t right.

b5 Kb6
Rd6+ Qxd6

b5+ Ka5
b6+ Kxb6
Rd6+ Qxd6

b5

Qxh4+

Nf2+ Bxf3+ Qh2#

Hmm, maybe not the design!

I disapprove of d4 on principle. My owner plays it though 🙄.

Thanks Maurits. I do have a coach, who I am seeing later.

Of course, the Old Testament of QGD books, to which all must look, is GM Matthew Sadler's. This is a fabulous book; according to my owner, I should stress. And Neil McDonald’s book is good too, especially for explaining some ideas (less good for pawn structures though).

Grooten is the most useful, most informative & user friendly. If you want just one book to learn the QGD to a good level where you can play and enjoy, this is the one to get (but see next post on GM Sadler).

Polugayevsky - despite the title, this covers more than the Orthodox (aka Rubinstein). Includes Tartakower, Lasker, Cambridge Springs, etc. Lots of theory & relatively little explanation. But valuable to check lines & explore. Useful if you really want to specialise & get expert in some lines.

2/5 Grooten - brilliant in covering all main QGD variations, explaining lots of ideas, with good use of diagrams & detailed exploration of pawn structures & plans. Lots of model games, some annotated, & some puzzles based on full games. No Slav, semi-Slav & QGA though.