I think a better way to put it is that all models are right given a situation / context / set of assumptions. It is important to understand the latter to apply the model.
I would highly recommend reading Chapter 3-5 (Epistemology) of Objectivism by Leonard Piekoff. It's a much more logical and easy to understand take on these same ideas.
In all seriousness, that is becoming one of my guiding principles (along with "divisions into categories are models"), so maybe I should pay more attention to this dude, except that he really is kind of hard to follow sometimes...