[dapids]

I'm not sure it was ever a particularly reliable approach to master instruction timings as these timings are a best effort schedule guarantee outside of a hard real-time system. Unless you profiled each instruction cycle timing over every microcode update to your processor, maybe, but I'm doubtful this was ever a sound approach.

It doesn't sound like grey beard knew what he was actually doing, but more relying on his years of experience and good fortune that has kept him with a job up until then.