Photos of Annie Doll in the Making found on Flickr

I think this person used the method of adding seam allowances by setting that button hole measuring thing and then you set it the distance you want and follow one side of the caliper type thing and then mark the outside.  It is then all equidistant. I've seen Nancy Zieman do this on wax paper to make patterns for fusing. 

http://www.flickr.com/photos/hettich/2837400653/in/photostream/