On the gumball when you click on the arrow tail square you get a window: "Scale factor in X direction”
It would be very helpful if the current length is displayed in the window as well. Take it one step further and allow designer to change that length. Now you have allowed designer to change the length two ways: 1) by scaling, 2) by a physical length.
Or does Rhino already do this?
I emailed this idea to McNeel and they said thanks, but post it here.