Very interesting. It happens that Pivotal Tracker https://www.pivotaltracker.com/ https://www.pivotaltracker.com/, (full disclosure: from my employer Pivotal L

Very interesting. It happens that Pivotal Tracker https://www.pivotaltracker.com/ https://www.pivotaltracker.com/, (full disclosure: from my employer Pivotal Labs), is built to combat this bias via the concept of "emergent iterations." You specify "points" for each fine-grained task, and tracker determines your velocity over time in dealing with these tasks, and predicts future progress. Therefore, the question for the user is "what other tasks is this task like?" at which point tracker can be the external observer, noting how long those tasks actually take. Interesting stuff, so I wrote a short post on this: http://pivotallabs.com/users/woosley/blog/articles/724-pivotal-tracker-and-the-planning-fallacy http://pivotallabs.com/users/woosley/blog/articles/724-pivot...