Feyerabend's position was far more radical. He (and, again, I'm trying not to misrepresent him, but I haven't read any of his stuff in decades) was trying to show that science is no more rational than anything else that people do, that scientists accept or ignore evidence arbitrarily, and that the existence of a scientific method is a myth. He was wrong, and the Galileo stuff is a good example. On the one hand, you have, not just Galileo himself, but a bunch of other people, observing very specific things, and the same things, repeatably; things that have natural physical explanations. On the other hand, you have some people who didn't see anything, or just a blur. You're right that there was little experience of looking through telescopes. But the failure to make an observation is not an observation. That scientists were influenced, in their model building, by observations, even in the face of the inability of some people to make them, does not mean that science is irrational. That the course of science is complex and mired in politics doesn't mean that there is no such thing as a scientific method.
Yes, I can dig up references if someone asks, I'm just lazy atm.