Unfortunately, he offers no source for this statement. Stalin's unattributed quote is indicative of a larger and somewhat frustrating phenomenon which is especially noticeable in the Prelude. Zhukov's fears, thought Stalin, were unfounded. I know that Army Group Center is the pivotal German force, and I know where Smolensk lies. And Malinovsky's army still awaits its orders.
Competition is healthy, especially if it produces wholesale German defeat.
But the time has come for Zhukov to produce that promised victory for which he has yearned so long. While it certainly leavens the text with interesting passages, this device also lends a certain pop flavor to a subject that some readers might feel deserves a more scholarly approach. Fortunately, it is employed less generously after the lengthy Prelude. After that uneven beginning, Zhukov's Greatest Defeat turns into a topnotch effort with the added bonus that, rather than rehashing the same old campaigns, it breaks new ground and brings a fresh sense of discovery and satisfaction while dispelling officially-induced amnesia. Vigorous descriptions of the tactical conduct of the campaign are carefully balanced with analytical discussions of the strategic setting as well as the personal perspectives of cold, frightened riflemen and tankists on the ground.