I've had some dozens of viewquakes, most minors, although it's hard to evaluate it in hindsight now that I take them for granted.
Some are somewhat commonplace here: Bayesianism, map–territory relations, evolution etc.
One that I always feel people should be shouting Eureka — and when they are not impressed I assume that this is old news to them (and is often not, as I don't see it reflected in their actions) — is the Curse of Knowledge: it's hard to be a tapper. I feel that being aware of it dramatically improved my perceptions in conversation. I also feel that if more people were aware of it, misunderstandings would be far less common.
Maybe worth a post someday.
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