Good Software Development Habits

> It's better to have some wonky parameterization than it is to have multiple implementations of nearly the same thing. Improving the parameters will be easier than to consolidate four different implementations if this situation comes up again.

Hard disagree. If you cant decompose to avoid "wonky parameters" then keep them separate. Big smell is boolean flags (avoid altogether when you can) and more than one enum parameter.

IME "heavy" function signatures are always making things harder to maintain.

I think it's especially bad advice with the "copy paste once is okay". You absolutely do not want multiple (even just two) copies of what's meant to be exactly the same functionality, since now they can accidentally evolve separately. But coupling together things that only happen to be mostly similar even at the expense of complicating their implementation and interface just makes things harder to reason about and work with.

Every time you consider copy pasting, you should be asking yourself “if the stuff I’m pasting needs to change, will I want both of these places to change?” It requires some guessing the future, but usually it’s not hard to answer the question.

IME if something should be an independent function or module, I rarely get to the point of considering copy/pasting it in the first place. If I want to copy/paste it’s usually because the two places currently only incidentally need the same code now, and my gut usually tells me that it will no longer be the case if I have to make any sort of change.