While that is undeniably an important issue, personally, I would pick this as the more important point in this particular context: "My code traded the ability

While that is undeniably an important issue, personally, I would pick this as the more important point in this particular context: "My code traded the ability to change requirements for reduced duplication, and it was not a good trade. For example, we later needed many special cases and behaviors for different handles on different shapes." The reason for my choice of this point is that provides a direct, technical counter to one of the simplistic technical rules on which the Clean Code movement is founded, and so might make a impression on someone who has, heretofore, regarded the case made by Clean Code proponents as irrefutable. That's also why I say "in this particular context", as in the broader scope of software development practices generally, the interpersonal dynamics of the organization are almost always more important than coding style.