I find when I am using block move and I am zoomed out pretty far I will sometimes make the selection. Then type on the keyboard 8 for 8 inches. And then push the left arrow key to move it 8 inches to the left. And then find that when I use the home key to complete the move it tacks on an extra inch and even says it moved over 9 inches.
I believe that sometimes it is 1 inch less as well. I also should note that I have the cursor options set for the cursor movement to be on a 1 inch grid if that matters.
I also find that if I zoom in before finalizing the selection that I don't experience this extra 1 inch movement.
Anyone else see this kind of behavior or is it just mine?