And just like the rule that it replaced, the rule of three is now often interpreted as the "correct" approach always, while I still find reality to be more nuan

And just like the rule that it replaced, the rule of three is now often interpreted as the "correct" approach always, while I still find reality to be more nuanced. Sometimes you do have the domain expertise to make the judgment call. A recent example that comes to mind is a payment calculation. You can go ahead and tie that up in a nice reusable function from the get go - if you've ever dealt with a bug where payment calculations appeared different in some places and it somehow made it in front of a customer you're well aware of how painful this can be. For some things having a single source of truth outweighs any negatives associated with refactoring.