While I was advocating a good definition of "Done" to enable you to measure progress along a path, Andy's point seems to be that many teams don't establish enough of a path. He says:
In my opinion, most agile teams aren't doing "Test Driven Development", and they aren't doing scrum iterations where they plan everything in advance. Instead, they are doing "Release Driven Development." They focus on assembling releases, and they do a lot of planning inside the release cycle.
This is probably true in more cases than not, though one could argue whether if you are not doing iterations or TDD whether you are, in fact, doing agile. But even if can concede (which I'm not sure if I am) that you can do agile without planning and acceptance criteria of some sort, what Andy describes above still sounds like it has an element of plan, execute, adjust, though perhaps in a more chaotic way than a "textbook" scrum process, and and perhaps at a smaller scale. So knowing having a clean definition of what you want to do is still important. In the Indivisible Task
I discussed how teams get stuck with planning because it's difficult to think of tasks that are small, discrete, and which produce useful work. It is possible to do so, but it is hard.
Perhaps the disagreement here is more of a misunderstanding. I consider being able to measure progress in terms of completed work items an essential part of gathering the data you needto improve your process and understand how to be more agile. While doing it at a macro (sprint) level is good, doing it on a day-to-day or hour-to-hour basis is essential. If you do this at a fine-grained enough level, and have a good testing infrastructure, you can release software more frequently. So, at the limit, perhaps Andy and I are talking about the same thing.
Since I only summarized, I encourage you to read what Andy has to say
for yourself. And I look forward to hearing comments both from Andy and other readers.