Like a lot of others here, I don't use astrology with tarot. But it's not because I'm not familiar with it. I actually had a pretty good background in astrology long before I ever picked up a tarot deck. As I learned about tarot, I eventually learned about the astrological associations with it and, to me anyway, it never rang true. I agree with Paul Huson (and Carla) that astrology was tacked on after the fact, and that it is not intrinsic to tarot. (I'd say the same about Kaballah.)
It seems to me that some people love to associate various systems of esoteric thought with tarot. I see cards with astrological symbols on them, and I've also seen cards with symbols for the Runes and the I Ching. I think people do this because it makes them feel that their deck is more "serious" than the next guy's. I don't think this is done out of snobbery by the way; I think they honestly feel that these associations give their cards a more spiritual and metaphysical connection to the forces of the universe. But I don't think they do. I think that those connections can only come from the reader.
The question I'm compelled to ask is: Weren't people doing tarot card readings long before the Golden Dawn crew were around? They used the Marseille deck, and other ancient card systems. Did those cards have astrological associations? Betcha they didn't. And the RWS meanings do seem to me like they could have evolved over time from the Marseille -- without help from planets and constellations.
I remember that, several months ago, there were a few threads here about the Meyers Briggs personality tests. A couple of threads were about assigning each personality type to a court card, like making the King of Swords an INTJ, or the Queen of Cups an INFP, etc. It seemed like a kind of mental exercise in understanding the court cards. But I am sure that if the Meyers Briggs test had been around in the Golden Day of the Golden Dawn, that the GD'ers would have found it irresistible to incorporate these personality types onto the cards.
To me, tarot is a system complete onto itself. And its meanings came, I would bet, from the people, from the peasants, from the gypsies, and the fortune tellers among them. That's my theory. Astrology wasn't involved. Tarot is its own esoteric system, just like any other.
My three cents.