The problem that McKenna was highlighting is that science has a bunch of unstated assumptions that impede actual fact-finding.
In the case of the radio the key was that there was a whole civilization (out of sight and not measured by instruments) that would need to be understood to figure out what was happening.
_That_ is the UFO issue in a nutshell.
The assumptions must be thrown away before a serious investigation can be started.
“The assumptions must be thrown away before a serious investigation can be started.”
I can see that angle, but I don’t think he’s quite correct. Science wouldn’t assume that there can’t be some other undetected civilization out there responsible for the phenomenon. That’s not one of the basic assumptions of science, or a conclusion that would derive from any basic assumption of science.
Science probably would assign that a lower likelihood and a lower priority to investigate, but the beauty of the method is that eventually, as the higher priority and more probable explanations are ruled out by the method itself, those lower priority explanations would naturally take precedence. So there is no need to dump the scientific method, since just following it will still get you to the same place in the rare circumstance where the apparently higher probability solutions are false, and in most cases, the higher probability solutions are true, so following the method, on the whole, is more efficient.