Thank you, Alexander, for posting your dialog with Gary Weber on the topic of nondualism. I know we have had other dialogs here on nondualism, but I was surprised to find that we had not created a section here for this topic, so I started one, and moved your enquiry to it here.
My primry critique nondualism is there are esentialy two basic forms that nondualism takes. One is contemplative and the other is strictly cognitive. My essential position on contemplative nondualism is any contemplative that seeks depth is essentially nondual because the experience of depth in meditation produces progressively nondual states where the identity is shed in layers as one enters into progressively deeper states.
My critique of cognitive nondualism is it is simply superficial and represents purely a cognitive effort of self enquiry. Here cognitive nondualism becomes simply a trick of the ego in pretending it is nondual. One cannot truely shed the identity by using the mind to attack it. And, one is not going to shed the mind or identity when one only resides on the surface, which is where cognitive nondualism. In conclusion without cultivating deep meditaiton states one is forever stuck in the superficial mind of pretence.
Just because Gary Weber had a single OOBE experience while attending a Zen meditation retreat does not say much for Gery Weber's otherwise superficial pursuit of the nondual state. After all, Zen completely rejects all forms of deep meditation after the stilling of the mind, and they believe the stilling of the mind is all too rare an experience, thus Zen Buddhism is fairly superficial, but at least they practice meditation, but all the while doing everything they can to avoid depth in medititation. Cognitive Nondualism is the same way, it resides forever on the surface mind because they do not practice meditation, and therefore have no idea of depth in meditation.