A very good article by John Heron, that I want to focus on one particular part, quoted below:

Wilber's first warrant for his four stages of the spiritual path tries to disguise training in a hierarchical spiritual school as peer spiritual inquiry. It presents what is in fact teacher-run experiential training as if it were peer group experiential inquiry, and teacher assessment of skills as peer validation of data. The teacher in experiential training tells you what experiences you are able to have, tells you how to have them and checks whether you have had them. The peers in an experiential inquiry ask whether a defined experience is what it claims to be, enter the experience in ways that are open to falsifying the definition, then check with each other to see whether their experiential data does or does not support the definition.

What Wilber calls consensual validation by checking with others is really teacher-dominated assessment of training outcomes. And this is not at all the same as confirmation or refutation in a peer community of inquiry. It is important to note that the peers, in such an inquiry, do not validate experiential data. That is, they do not confirm or refute their experiences in the light of the original idea - that is peer assessment of learning. They do the opposite: they confirm or refute the original idea in the light of their experiences - and that is peer inquiry.

Wilber refers to Zen as an example of trascendental inquiry. Zen, however, is a training run by a Zen teacher who has himself had ten to twenty years of training within a very strong, long-standing and traditional lineage. This powerful tradition has both cognitive and technical authority: it defines both what experiences mean and how to have them. Zen is training people to grasp the notion of satori, then ungrasp it and have the experience of satori, and is then assessing whether they have had the experience - an assessment dominated by the Zen master. The only 'bad data' that are rebuffed are experiences that are not in line with traditional experiential claims. Zen training, in its traditional oriental form, is not a collaborative inquiry as to whether satori is indeed what it claims to be. It is an hierarchical not a peer process. It is not practising openness to experiential data that could falsify or modify or lead to a reconceptualization of the satori claim.

(2) I take the view that experiential training and experiential inquiry are always to some degree involved in each other. They range along a spectrum between theoretical extremes of all training at one end and all inquiry at the other. In experiential training, the training component is greater than the inquiry component, and this occurs when the trainer gives more technical (how to do it) and conceptual (what it means) shape to the trainees' experiences than the trainees do individually and co-operatively.

Experential training versus experential inquiry.  For me, John Heron seems to have the right of it, in conflating these two. 

However I would like to inject a thought, perhaps more of a question.

This distinction - experiential training versus experiential inquiry is the essence of the distinction between modern intellectual inquiry and traditional intellectual inquiry.

Everyone reading this is most likely committed to this modern understanding of intellectual inquiry.  Still, for balance, I would encourage everyone to read Rene Guenon, for an exigesis on the distinction.  Especially The Crisis of the Modern World.

Herre's the thought.  In the current world of experiential inquiry, the world is GIVEN.  The world is here, "since beginningless time", to use the vendantin phrase.  It is because of this givenness, this "hereness" of the modern world, that we can perform experiments on it, find out new stuff about it.

For traditional modes of spiritual experiential inquiry the word of the guru who KNOWS is considered the "givenness", in parallel to the physical world's "hereness".  That's the bedrock against which to measure spiritual progress, the same way referencing the world that we are in is the bedrock to measuring technical, worldly progress.

This is a subtle distinction that I agree, Wilber SEEMS to conflate.