What does the Toyota manufacturing process have to do with riding?

A lot - actually! Just replace 'yellow' and 'red' with 'half-halt', 'halt' and/or transitions:

[Toyota calls] stop and fix the problem "jidoka". It's a process where people are asked to identify every instance where the situation doesn't match the expectation. They do that by "pulling the cord" to activate an "andon" -- a signal. There are three signals: green (all fine), yellow (come look at this), and red (I need help). Operators in the Georgetown, KY plant pull the cord up to 1000 times/day.

Well, that just shows again how you can apply expertise gained from other areas to riding (For those of us that always have riding somewhere on the mind!).