Zhukov can best be described as 'shrewd' in dealing with Stalin. Unfortunately, having to operate with a degree of self-preservation meant that in certain instances, when Stalin held certain convictions one way or the other, Zhukov failed miserably in attempting to change the Dictator's mind. Here's an example of when he wasn't able to impose his personality on the dictator:

When Operation Barbarossa stalled out, Soviet counterattacks on Army Group Center showed success, driving back the Germans and creating some breathing space between the German front-line and Moscow. Stalin greatly over-estimated both his army's capabilities and the German's disorganization and ordered an expansion of the counterattack - Zhukov argued against, he failed. Most sources I read say that Zhukov failed to convince Stalin because other generals, like Timoshenko, agreed, and like most dictators, Stalin only listened to what he wanted to hear in many instances.

Zhukov definitely talked baldly to him when Stalin could handle it (Stalin was well aware of the blatant brown-nosing of most of his subordinates, and half-admired Zhukov's straightforwardness) , and spoke softly when he was in a towering rage. The sources you've read that stated Stalin felt Zhukov was one of his best general's is quite correct and the proof's in the pudding on that one: Zhukov seemed to become, especially early-war, his go-to fireman, flying from one crumbling front to another to assume command, stabilize the situation, and then return to Stavka. Everything I've read suggests that Zhukov, from early on, was capable of 'reading' Stalin and working around his personality; but he was still relieved of command a few times when Stalin truly hit the ceiling - even understanding how the dictator worked was not protection enough.

Sources:

Operation Barbarossa: The German invasion of the Soviet Union; Kirchubel, Robert

Stalingrad; Beevor, Antony.