Daniel B Markham makes a great point about the tools, concepts, ideas, etc. that developers are sold under the guise that it will help them:
The problem is that we developers have become a market, and like all markets, people are trying to sell us stuff. These people do not have our customers in mind -- for them we are the customer. Instead they have us in mind.
People try to sell us stuff based on whether or not we want to consume it, not whether or not it's useful to the people as programmers we are trying to help. This creates a bit of perverse incentives.
The money line:
It's definitely important not to get caught up in dogmatic theories about development practices and tools when working to deliver a startup product. But, at the same time, don't go too far the other way. Different startups unfold in different ways. Some are sprints, which either succeed or fail very quickly. Others are marathons, dragging on for years before finally emerging out of the flat part of the hockey stick curve.
Of course, one might argue that all startups should be structured as sprints towards resolving a series of hypotheses...
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