With the context you've provided here, this is still an estimate-able task. The steps to do this task are enumerable and would be similar across similar tasks.

With the context you've provided here, this is still an estimate-able task. The steps to do this task are enumerable and would be similar across similar tasks. I believe that the conclusion "software estimation can't be reliably done" comes from a standpoint that claims tasks like these ("reverse engineer X-Y-Z...") are somehow completely novel each time we encounter them. In my experience, they are not... even "soft tasks" like "design a Thing" and tasks with unknown details like "reverse engineer X-Y-Z..." -- when you do them more than once -- will be seen for the predictable beasts that they are. But only if you approach them with the attitude that they aren't these novel beasts. That almost all of the work of the working practitioner is NOT like that of the researcher on the bleeding edge of some novel discovery.