It seems to me that it would be better to address step 6, where programmer B adds cruft to the abstraction rather than re-working it. I appreciate that pragmati

It seems to me that it would be better to address step 6, where programmer B adds cruft to the abstraction rather than re-working it. I appreciate that pragmatics sometimes dictates that duplication is the right option, but instead of mostly giving up and advocating an emphasis on duplication, I'd rather encourage better design of abstractions in the first place, and more willingness to genuinely improve abstractions later on if necessary (rather than more complex logic or whatever). Especially with abstractions as small as methods – I very much question preferring duplication in cases as small-scale as those. This may depend on the expressiveness of the language you're using, though.