Comment by p0w3n3d

look at the roman roads and compare them to the contemporary ones. Those ancient roads are superior in some aspects (unbreaking, not filling with water etc), and still people try to find out how were they made.

Having that said, I agree with you: the forgetting of the technology was not a direct reason of the fall, it was a feature though...

I'm from Poland, and I have comparison with my colleagues from east. They can fix things we've already forgot how to fix in Poland. My friend fixed a broken Sony TV with a microscope and a soldering gun. I'd pay just 1000$ for the new TV, as he got advised in the official repair store, but since he was Russian, he fixed it by himself.