I think I remember a Carmack tweet where he mentioned in most cases he only considers it once he reaches three duplicates

DRY and KISS were right next to each other which I thought was funny.

I worked for a company that also had hardware engineers writing RTL. Our software architect spent years helping that team reuse/automate/modularize their code. At a mininum, it's still just text files with syntax, despite rather different semantics.

I've heard that story a few times (ironically enough) but can't say I've seen a good example. When was over-architecture motivated by an attempt to reduce duplication? Why was it effective in that goal, let alone necessary?

DRY is misunderstood. It's definitely a fundamental aspect of code quality it's just one of about 4 and maximizing it to the exclusion of the others is where things go wrong. Usually it comes at the expense of loose coupling (which is equally fundamental).

The goal ought to be to aim for a local minima of all of these qualities.

Some people just want to toss DRY away entirely though or be uselessly vague about when to apply it ("use it when it makes sense") and thats not really much better than being a DRY fundamentalist.

Why do the have to be so smart but so annoying at the same time?