> But the solution is NOT to throw out a bunch of those old layers and replace them with new layers!!!

Neither is keeping everything as it is and keep pretending it's fine!

> When you throw away code and start from scratch, you are throwing away all that knowledge.

I disagree with Joel on here. There's lots to be learned from throwing everything away and starting from scratch, and if anything those innovations could make their way into the current infrastructure, as it has happened with Midori and Windows.