The QGA is a positionally sound and reliable opening, played by world champions Kasparov, Karpov, Anand and Topalov.
The authors consider the Classical System with 3.Nf3 Nf6 4.e3 e6, but they in fact prefer alternative, sharper approaches.
Against 3.e4 they recommend 3...Nc6 4.Nf3 Nf6!?, against 3.e3 they choose 3...e5! and against 3.Nf3 their weapon of choice is 3...Nf6 4.e3 Bg4!? Other choices and drawish alternatives are given.
They pay special attention on the ideas behind the moves, leaving the detailed coverage for their "Step by Step" sections.
You'll also find advice against Queen's pawn openings where White refrains from 2.c4.
Alexander Delchev is the European Grand Prix winner in 2004. He has played in many Olympiads for Bulgaria. His best Elo was 2669, current rating – 2604. Delchev is the author of The Most Flexible Sicilian, The Safest Sicilian, The Safest Grünfeld and The Modern Reti.
Semko Semkov played for Bulgaria in one Olympiad. He is a chess journalist and theoretician. He has authored Kill K.I.D. and four other books.