When I see these TTL CPUs made from very few chips they leave me scratching my head. If it was this easy to build a fast 8 bit computer with a small number of the 7400-series logic chips that were available at the time, why was everyone so jazzed about the introduction of the 8080 and 6502?
The thing is it wasn't easy, it was merely possible.
It seams easier now because we have much better access to information and ideas that were much harder to come by. The Gigatron was a team effort, that team wouldn't have come together without the internet. I'm not sure when that particular ALU design came about but the idea of sticking 8 multiplexers and 2 adders together like that was a little bit of genius in itself.
