We had a procesor design course at the university. Single participants made 68k complexity designs, groups went to 286 and more complex parts. It was 6-8 hours workload every week for 4 months. A year time is a lot! Manufacturing technology is another issue. Same design will deliver different results on 28 nm and 160 nm nodes.
What I wonder about is the 10x factor here - all of these designs have already been invented and are available for perusal. How many people could come up with something like this with nothing but a knowledge of mathematics?
I sometimes don't even know if I could invent the wheel if it wasn't already invented.
