I don't know who Kurt Grandis is, but I'd like to buy him a beer. From his post:
Almost two years ago I was in a rather unlikely situation in that I was running a software engineering department containing both a C# team and a Python team...It slowly dawned on me that I had a perfect test bed. Here we had two teams using different technology stacks within the same department...they shared the same development processes, project management tools, quality control measures, defect management processes. Everything was the same between these groups except for the technologies. Perfect! So like any good manager I turned my teams into unwitting guinea pigs.
The result? And yes, those velocities are normalized---see the full article for details. A couple of commenters have used his report as an excuse to re-hash the whole "open source is better than Microsoft", but I think the real story is more interesting: by working and measuring in short chunks, even a small software shop can collect enough data to make decisions with real business impact.