Freud was incredibly popular because his work resonated with the experience of millions of people. Clearly he's been validated: he didn't need empiricism. Sometimes that happens with smart people. Not all of his ideas are right, but come on, it's psychology, and much of biology isn't right either.

Sorry if I'm being naive, but by this standard L. Ron Hubbard has been 'validated'

I'll tentatively accept that Dawes' work has been spotty (I do suspect that there might be some side-effects from psychotherapy, not related to the main theories, that should have been picked up). My problem with Freud that some of his core theories (sexual desire for the mother being the prime example) might well be bunk (strongly suspect this due to evolution having no reason at all for such a thing), and he never cared to check.