I'm experimenting with the various offset feature types (edit -> offset -> button on the dashboard for different types) and I think that the offset with draft is just what I need. I'm trying to offset a contoured quilt, with draft and it's asking me to define a sketch. Why? I cannot even think of what a sketch would do for me here so I can attempt one and see what happens.
The help files only tell me what the button does - that I use this button to define a sketch. Duh! But what does the sketch actually do in an offset with draft on a quilt?