Most Awesome people to follow, the #ale13 version Part II

Yesterday I posted about two people whom I think everyone interested in the topics of this blog should follow. I've met them at #ALE13 this year and am impressed with the work that they are doing. Today I'll recommend two other people to follow:

• Kurt Haeusler: Kurt had a great presentation today on Offers and Pricing in Agile and Lean Software Development. The content of the presentation had many insights, but the one that stuck with me the most was his comment on how Lead Time (the time it takes to deliver something to a customer, starting from the moment they customer as asked for it) is affected by far more significant factors than what is typically calculated when estimating a size for a User Story. The basic argument is: there are many factors that affect delivery date that have nothing to do with the time it takes to develop and test the functionality. Therefore, Throughput and Lead Time are much more important metrics than what we may think something takes to code and test. To this already convincing argument, he added: "and random events within a system also affect Lead Time". A light bulb went on in my head: this is a clear argument for the #NoEstimates approach I advocate.
• Jurgen Appelo: Jurgen has been active in the Agile community at least as long as I have, so you probably already know about him. But the work that he is presenting on Tribal Businesses has the potential to revolutionize our industry. The cool thing: he is implementing his ideas through the Happy Melly project, so you will be able to follow his progress directly. I'm also involved in the Happy Melly project.

Who will you start following from the #Ale13 crew? Share their twitter handle/blog URL and why!