I think the usability aspect of this project was a challenge, firstly the vast majority of literature on usability testing is based around web based development and does not allow for the complexity of actual physical development
Secondly these kinds of “post-optimal” products such as Presense, do not follow the conventional forms and idea’s of “traditional” electronic product development. They are not rational products therefore cannot be designed by purely rational means and in this way designing them specifically round a user can often prove wrong for the product. I think areas of functionality around a device are aspects that can be tested by users and judged on the results but when designing products hat are intended to alter people perceptions of, in this instance, the way they communicate, this is something that in many ways does not suit this style of development.
For this reason I think the usability tests like the participatory design and the more “experience” based prototyping is what suits this kind of product best
