Rotating Around 3D Cursor (Object vs Edit Mode confusion) In object mode, if I rotate an object about the 3D cursor it acts exactly as I expect. It rotates around the cursor in a circle, like this:



But in edit mode the behavior is completely different. I don't understand what's going on. I am trying to rotate some vertices around the 3D cursor, but it doesn't rotate in a circle. It does this:



I should note that those vertices are connected to a large mesh that is hidden (I suspect that has something to do with this behavior). 

As you can see, it goes inside of the sphere. As if the distance from the cursor decreases as it rotates. What is going on? And how can I rotate vertices in edit mode the way an object rotates in object mode?

Note: Transform orientation is global, and pivot is 3D cursor in both modes. Proportional edit is OFF in edit mode. 

Thanks!
If the subdivision modifier is working, and you toggle the editing view in the modifier panel, the mesh displayed in 3D view will not be the one you actually manipulate.