I don't think there is too much danger of that unless you try to find the zero point with the grinder on!
Anyway, I was sort of wondering the same thing.
When I got my Rocky 2 weeks ago, I found that the expresso range seemed to be between 4 and 8 (at least for the couple of bean combos I was using. (And I'm getting great press-pot grinds at about 42-43.)
Later, I took off the hopper and found that the zero mark on the dial was actually not at the point where the upper and lower burrs actually touched. There was a \"safety\" screw preventing this. After removing the top burr, cleaning the coffee residue, then manually turning the burrs until they touched together, I would have to estimate that this occured at what would be about a -3 or -4 on the dial.
Is this about what others are experiencing with the new Rockys? I see no point in going through anymore trouble to actually zero it as it seems to grind fine enough as it is, and the extra margin of safety is probably a good thing.
I tear my Rocky apart on a regular basis for cleaning
and I have set it up in such a way that I can ZERO burrs - not sure if I want to print that process here in the odd event that someone harms themselves or creates a rip in space time.