As someone who formerly ran an audio service center, I fully agree with your point.Logic can lead you anywhere, depending on the assumptions. All conclusions, opinions, and perspectives are based upon the prior knowledge, beliefs, and underlying assumptions that are often simply accepted without question. These are great examples of how a statement taken as fact, then applied out of the context can be used to generate the desired logical outcome. It IS logical IF you accept the premise, and the unstated assumptions along the way.
Many of the debates that we find in the A/V business revolve around opposing underlying assumptions, with far less testing of the limits of the viability than needed to come to the conclusions that many reach. Many of the problems that people have trouble solving also have their root in faulty assumptions. We see it all the time in service. We operate on limited information and make assumptions constantly. When we fail to test them, it can often create more headaches. The real problem is when someone is incapable of understanding that everything that he/she believes about a particular matter is based upon some set of assumptions.