My guess is that the code will come back, somewhere betweeen 1 and 3 weeks. The nature of the 2-trip detection logic means that some "trips" do not count as a trip, and with an intermittent problem, it takes a while for the problem to occur on 2 trips that qualify as an actual trip - driving x miles, after y hours cold soak, reaching proper operating temperature, engine RPM over z, etc.
I agree, a few probably won't matter much. A side effect of Toyota's very consistent assembly methods means that there are very few "one of a kind" problems. In other words, when the design or assembly or manufacturing method is good, then almost no cars will have a problem, but if there is a problem with the design or assembly/manufacturing method, then almost every vehicle will have the same problem.