[kbenson]

I'm not so sure about that. I think a complete rewrite is easier if you correctly separated concerns and compartmentalized needs. OOP is supposed to enforce/encourage that, but it's fairly easy to not treat your objects as black boxes with APIs, and then you've put constraints on replacing a component. Procedural code doesn't necessarily tout it's ability to encourage that, but well planned and implemented functions can give you the same benefit.

In the end, it's all up the the programmer.