You ever play Steel Beasts? That's my teacher right there. A T-64B COULD drive up the crest to hopefully get its gun in place, but in the process, it exposes its hull to an unsatisfactory degree, and likely gets shot for its efforts, not to mention skylining itself beautifully to be easily seen by anyone watching. Yes, it does matter. It measurably decreases the amount of time one can make use of the position, because being so exposed you will die much more easily to return fire. Incidentally, this makes reverse slope defenses extremely effective against Soviet style tanks.
And yes, the Soviet tanks could try other things, however due to their design, they can't take advantage of other, probably superior options.
And if we go by the Soviet's own thoughts, they're not really going to be doing much defending from prepared positions anyways. Meeting engagements were everything to them. >The primary advantage here...
Disagree somewhat with this. This is certainly a huge factor and plays into the biggest factor for success, but it is not said factor itself. That would be whomever spots the enemy first is likely to win the engagement. Studies have indicated this to be the predominant factor on who lives and who dies. If you're in a proper hull down position, you severely limit the amount of yourself you're showing, and if you've got the chance, you'll be going either turret down or completely down into a hide position, to keep yourself hidden until the moment you strike. This aids in the defense to a much greater extent. Imagine watching a ridge that you're advancing towards and suddenly out pop 4 turrets and start blowing you away. Contrast this with Soviet style, where the tanks would have to drive all the way up, exposing themself to observation and fires before they can fire back. And sure, ambushing is a very powerful tactic. However, if the engagement extends far beyond that initial shock, you're going to wish you were hull down.
Sweden says hi.