The execution (how) can be 'mechanical' but the goals and choices (why) should be thoughtful. If it's simply deduplication there is no thoughtful why necessary, although in the worst cases abstract machinery is created for the purpose.

You're right about my misconstruing 'no behaviorial change' as that is always a requirement. There should however be a change in where the seams of the implementation lie which better suits the direction of expected changes.