The stuff by Mitchell Whitelaw on "Generous Interfaces" (and he cites some aspects of Trove as an example of a generous interface) seems relevant to this discussion: Slides: http://www.slideshare.net/mtchl/generous-interfaces Paper: http://www.ica2012.com/files/data/Full%20papers%20upload/ica12Final00423.pd f Owen Owen Stephens Owen Stephens Consulting Web: http://www.ostephens.com Email: [log in to unmask] Telephone: 0121 288 6936