A few years ago I went to an astrology meeting. Dark sky, Saturn clearly in the legs of Leo. Very pretty... I go in to hear that saturn is in Virgo. Put me off astrology a few months. I've made horoscopes and the success rate is higher than probability as I see it. Off 24degrees and they still work? I think we're looking in the wrong tree. astrology is a lunar effect with the sun as the other prime mover. The planets etc are bells and whistles. At any given time or date, the moon is where it was one rotation, (28) days ago.
The sky behind shifts but the location is the same. Also, looking at an ephemris for any given day over the years, the moon switches signs about every year to the next of type. example, from American Ephemeris for the 21st Century, June 1st, 2000... 19 Taurus, Jun1,2001...7 libra.June1,2002...17 aquarius.2003, 19 gemini. 2004,10 scorpio. 2005, 29 pisces. and so on.
These being the moon at midnight. It dosn't matter what type of astrology your using cause the moons in the same old place.
Finally, we use four elements so they tend to run in threes, as they do for air in the above example. The asian system uses five so they tend to pair. I suspect this is the origin of the stems in the stem/branch system.
Sorry for the length thanks for the patience.
Craig