I stumbled across this by Larry Osterman in Bloglines where he points out a curious entry in the project schedule for the next version of Windows. As Larry points out it is interesting terminology but its a really apt description for what the Order of Magnitude field in Scenario work items for the MSF Agile process template can be used for – it is certainly how I approach it. I have this theory that the more you try to refine the estimate the more chance you have of getting it terribly wrong. As time progresses you get a better feel for how accurate the estimate was and you can adjust your schedule accordingly.
Here’s to T-Shirt sizing (even if Larry doesn’t like the terminology :P).