z170 pro4 LLC and Offset mode bug?

LLC:  According to the graphic in the bios, it appears that LLC Level1 should provide the least voltage drop (highest Vcore under load) of the 3 settings available.  I find exactly the opposite.  I have the highest voltage difference between VID and Vcore at Level1, slightly less difference (i.e. higher Vcore) at Level2, and then the highest Vcore at level3 which is also the lowest gap between VID and Vcore.  This is running at 4.5GHz i7-6700k using Auto voltage mode.

Am I completely confused or is this backwards from what is shown in the bios image about the behavior of LLC levels?  Shouldn't level3 allow the most voltage drop at high load?  Why is level1 allowing the most voltage drop at Vcore under load?

Second question is regarding Offset mode for overclocking providing a much lower voltage than expected at 0mV offset.  I've got my system running stable at 4.5GHz using Auto mode and LLC Level1.  I wanted to experiment with Offset mode to further lower the voltage and still be stable at 4.5GHz.  I started by changing just 1 thing, Auto mode to Offset mode, and leaving the offset voltage field at Auto (which is between 5mv and -5mv) and thus I interpret at 0mV offset.  

I was expecting my system to produce the same VID and Vcore under load as it did in Auto mode, but I find that Offset mode is producing a VID 130mV lower than it was under the same load in Auto mode. My VID in this mode is only at 1.19V under load where it was previously 1.320V using Auto mode. My system soon froze after getting these readings.

Am I completely confused or is this strange behavior for Offset mode considering I'm using no offset voltage? Any thoughts on what could be going on?  As an aside, on the next boot after my freeze Windows7 OS became corrupt and would not boot, forcing a re-image.

Thanks!