Earlier quoted context omitted.
> They are almost always a source of distraction, people start to argue about the analogy itself instead of the topic at hand, which is almost always completely counter productive. My experience is that this is very true among a certain group of people, particularly literal-minded software enngineer types. But it is much less true in the general population where a single good analogy can accomplish more than pages of…
My experience is analogies are erroneously as supporting arguments to jump from premise to conclusion of an unrelated topic. I saw them a lot at my family's various religious/cult gatherings when I was a kid. The preacher would state something and then "prove" it with an analogy. Analogies don't accomplish anything in basically all of the uses I've seen. People want them to serve as proof, but it's a lazy way of gett…
Analogies are an attempt to generalize an argument. Say we are trying to prove that "It will rain" is a valid conclusion from "If it is cloudy it will rain and it is cloudy". We can generalize this to "A -> B" & "B" -> "B", which you will recognize as an application of modus ponens from formal logic. Analogies try to use this power on fuzzier topics.
A normative principle like "We should build a new post office" are so abstract that they cannot be tackled head on (try defining "should" in the comments section and having no one point out a flaw to see why this is difficult). Because of this, we try to make comparison to other, seemingly similar, cases in an attempt to draw out the underlying logical structure. Because of this, I think they are a powerful and useful argumentative strategy.