The identification of astrology as an art is only to be expected, because once the math has been completed and all the charts are drawn up, there is nothing very obvious or necessary about any particular conclusions which an astrologer might infer. There are many possible interpretations which an "expert" might provide to a client and it is here that the "art" of astrology comes out.
...an astronomer knows no more about astrology than a radio mechanic knows about music. To ask an astronomer for his "expert" opinion on the subject is useless.
There are no hard and fast rules for interpretation, which means that there is no interpretation which is really "better" or more "objective" than any other. The astrologer improvises and plays things by ear. This is why astrological predictions are generally "better" when they are done with the client right there rather than "blind."
If the astrologer can speak to the client, it is possible to ask probing questions and see immediately any reactions to the developing interpretation. In this fashion, an individual predication can be tailored to the person at hand, taking into account their very real fears, hopes and history. When performing "blind," however, the astrologer has nothing to work on but the data itself and this never seems to provide quite enough for a really accurate or informative series of conclusions.