I think consistency in this context means the capacity to absorb insane training loads day in day out.
E: Should like to add that beyond speaking about the well established fundamentals (progressive overload, specificity, etc) pro coaches just put out propaganda. San Millan's zone 2 is the perfect example. It is simply bread and butter base endurance training. Everyone has always done it. A lot of.
When he goes beyond that, the model questionably attributes magic to certain intensities (the hallowed zone 2) and, being based on lactate, has metabolism backwards (even short bouts at lactate producing intensities, think hills, supposedly hurt aerobic adaptations and their dampening effect on aerobic metabolism supposedly lasts for a prolonged time during a ride). When eg Coyle and Coggan studied this in the 80s, this was not their observation nor conclusion.