Lasse makes a good point about my Elegant Sufficiency post. Defining design thresholds is hard, very hard. The only way I think they can be practically defined (or identified) is with reference to a codebase since design thresholds are implicitly embodied in the practices of a team and in the work they produce. This avoids the need for an official, written guide to good design for team X, which would be useless anyway.
The other main subject of Lasse’s post was to discuss the benefits of “asking the team” and voting to decide whether a particular design sits within the thresholds. I think this is necessary and a great way to encourage emergence of a common set of design thresholds. As to whether the thresholds will produce elegantly sufficient designs - well that sounds like the subject of another post. Off the top of my head I’d assume that this is where a “benevolent dictator” (or two) could do some dictating to help things along.