(Of the three volumes, I think the first remains in all aspects the best. But the whole trilogy is excellent and a sound corrective to Kershaw. It is the best and most judicious survey of the whole topic in English that I am aware of. That said, it is a long trilogy, and it is nice to have it behind me rather than before me.)
This book, as expected, is excellent -- and marks the entire trilogy as a valuable achievement. Evans is best when dealing with the more granular -- his treatment of the broader events of military/geopolitical history is solid, but appears derived. This is not, however, to detract from the value and interest of this book. In particular, Evans now represents the fullest and most modern refutation of the 'structuralist' approach favored by Kershaw, Broszat, and others -- according to which the Nazi's merely 'stumbled' into their crimes and misadventures. (See my reviews of Kershaw and MacGregor Knox)
His broad thesis here is as follows: The astounding success of German arms from 1939 through Summer of 1941 was ultimately due to their speed, boldness, and audacity -- applied to an unprepared opponent. But then in the summer of 1941, when the Central Group confronted the bulk of the shaken Soviet army before Moscow -- which was slowly beginning to firm -- Hitler blinked. He diverted troops to Group South to the Caucasus to secure the Romanian oil fields -- and by the time he returned them in the Fall -- the Soviet troops had stiffened, the rains had begun..., and winter was upon them. Momentum was stopped cold. And at this point, it became a war of attrition (371f.)
But a war of attrition is something the Germans could never win. To give just two sets of statistics: Airplane production. By 1943, Germany was producing about 26,000 aircraft per year. But in that same year, the British produced 35,000, the Russians produced 37,000, and the U.S. about 100,000. Combined allied machine gun production that year was over 1.1 million; Germany production just 165,527 (332f.). The GDP of the Allies to that of the Axis (combined) was never less than 2:1 and, by 1944, was more than 3:1
And so, by 1941 Winter, the War was essentially lost -- a massive push the following year (Stalingrad) notwithstanding.