and instead the differences were caused by 'incomplete' netlist simulation code which worked fine for the 6502 but required some tweaks for the Z80 That was ve

and instead the differences were caused by 'incomplete' netlist simulation code which worked fine for the 6502 but required some tweaks for the Z80 That was very interesting to read. This is a nearly 50-year-old CPU, and yet many people are still discovering things about how it works in detail; or perhaps more precisely, discovering edge-cases in simulation and fixing the latter to more closely correspond with the actual physical processes it models.