You have to remember that at the time it was written, complete code re-writes were a lot more common and often had disastrous results. Sure, I've also complete

You have to remember that at the time it was written, complete code re-writes were a lot more common and often had disastrous results. Sure, I've also completely re-written systems in a way that wasn't disastrous. I'm doing one right now. But the legitimate case for it is sufficiently rare to deserve some extra scrutiny, even if it is a more fun approach for the developers involved.