As to the truth vs. idealized myth, which is which?
Truth is what happened, idealized myth isn't. Santayana said that those who do not study history are condemned to repeat it. History is the study of human actions. If that which we study does not reflect that which happened it is not history, it's just some fairy tale designed to make us feel good. If a historical figure is set up a peg or two too high then it is our responsibility to bring him down to where he belongs.
In the case that brought this discussion up it would seem that the perpetrator of the phrase "or as they're calling them today", at best misunderstood the point of The Founding Brothers, perhaps only having read the New York Times Book Review. That's not my concern here. I don't like it when the term revisionist gets thrown around as though it were automatically a bad thing.
