As someone who has done extensive graduate work in the field of developmental psych (I approach human development and cognition as a developmental constructivist), I believe I am qualified to discuss matters related to my field. However, I also believe my advanced degrees in said field do not give me the credentials to speak as an expert on the collapses of WTC 1, 2 & 7, the science of controlled demolitions, etc.
The same holds true for Mr Fetzer. While he is qualified to speak as an expert on the cognitive aspects of conspiracies and conspiracism, assuming I am not missing something regarding his background, he is just another commoner when it comes to understanding the technical aspects of engineering, physics, demolitions, building collapses, and so on. Unless I am misunderstanding the core content of what comprises a PhD in the history and philosophy of science, Mr Fetzer is best described as a philosopher and not a practitioner when it comes to the "hard" sciences relevant to understanding 9/11.
It looks like I have a different perspective on the exchange between Brass and Mr Fetzer. Based on the OP presented by Brass, from the outset, this clearly was not a PhD to PhD or expert to expert dialogue. It was a student to professor inquiry, ask questions to get answers. Nothing in the initial exchanges would lead Mr Fetzer to conclude Brass was approaching him as an equal in terms of professional/educational qualifications with the prospect of having an intellectual give and take. That said, if I was Mr Fetzer, I would not have expected Brass has read all of my papers/research at that point.
In fact, Brass states as much when he prefaces his initial questions with this: "To be honest, I really don't know if you support these claims, but figured I would ask anyway." Fetzer even urged Brass to send the inquiries knowing the responses were to be used as a "counter argument from the 9/11 "Truth" crowd to Brass's attempt to debunk the 9/11 conspiracy theories. While Brass could have offered more in terms of fully disclosing the depth of his convictions regarding debunking truthers, Fetzer was a willing participant in the agreed upon exchange knowing the facts I have stated above.
As the teacher engaging a skeptical student with his questions, I believe Fetzer should have approached this as an opportunity to convert a "skeptic of the skeptics," to borrow from his own terminology. Rather than give any credence to Brass's skepticism of truther theories as a way for Fetzer to show Brass he was interested in engaging in an intellectual discussion, Fetzer fires this mind closing salvo as if it is "the decided TRUTH":
"Your use of the term "Truthers" in quotes suggests that you are a skeptic of the skeptics, who do not merely doubt but have actually proven that what we have been told about 9/11 is not simply false but provably false and, in at least some cases, not even physically possible because it violates the laws of physics, of engineering, or of aerodynamics. I have published a summary of our findings as "Why Doubt 9/11?...." He then closes with this: "I spent 35 years teach logic, critical thinking, and scientific reasoning."
With these 2 statements, Fetzer has declared: The case is closed and I am on the right side, and remember, I am much more intelligent than you. Brass then fails to obediently bow at the Fetzer alter of truth and superior intelligence and even dares to challenge Fetzer's irrefutable laws of 9/11. Granted, Brass could have definitely used more tact in his rebuttal of Fetzer's answers. As a result, Fetzer feels compelled to resort to demeaning his intellectual inferior with his next response. Keep in mind, this all transpires after a few email exchanges within a few hours (I presume) on New Years Eve of 2010.
"I am going to put this as kindly as I can. One day when you grow up and discover that we were right and you were wrong, you are going to feel very differently about all of this. Your attitude about "Loose Change", for example, illustrates the problem. I was alluding to interviews done with firefighters, which is completely independent of your agreement or lack of agreement with its major themes. The fact that you are not even willing to watch the film speaks volumes. You have been massively duped by the many web sites out there dedicated to keeping the truth from the American people. I knew your attitudes as soon as I read your questions and how you framed them. I am sorry, but you could use a good course in critical thinking.
Best wishes for your project--and I look forward to reading your paper!"
Just my long winded 2 cents, from a life long student and one who has 7+ years of university teaching experience in my past.
What follows in the exchanges a year later is nothing more than a typical truther vs debunker debate with the appropriate jabs and personal insults to which I have nothing to add.