[digitalPhonix]

He’s not claiming the rewrite is a clean room implementation. In fact he’s explicitly saying it is not:

> However, the purpose of clean-room methodology is to ensure the resulting code is not a derivative work of the original. It is a means to an end, not the end itself. In this case, I can demonstrate that the end result is the same — the new code is structurally independent of the old code — through direct measurement rather than process guarantees alone.

[simonw]

That's a good note, yeah. Dan isn't claiming a pure clean room approach here.