An anonymous reader writes: An article at MIT's Technology Review makes the case that the complexity of the design tools behind 3-D printing are what's holding it back from widespread adoption. Many of the devices are indeed prohibitively expensive, but the inability for your average person — or even your average tech hobbyist — to pick it up and start experimenting is an even bigger obstacle. 'That means software innovation could be more important to 3-D printing than gradual improvements in the underlying technology for shaping objects. That technology is already 30 years old and is widely used in industry to create prototypes, molds, and, in some cases, parts for airplanes. ... Although additive manufacturing allows for designs that can’t be made easily in any other way—such as complex shapes with internal cavities—so far, companies have mostly used 3-D printing to create prototypes or models of familiar products.'