What an absurd article. The fact is, astrologers have always ignored constellation boundaries as defined by astronomers. They just divide the zodiac into 12 equal parts, assigning them the traditional 12 zodiacal signs.
If you use the constellation boundaries defined by the International Astronomical Union, the Sun actually moves through 14 constellations.
When I was little, I read a book that listed birthstones by zodiac signs. As an adult, I’ve noticed that birthstones are now listed by month. I used to do marketing for jewelry stores, and doing it by month does make it easier to plan sales.
I’m actually always surprised that the astrologers didn’t try to line the zodiac signs up with the months better, for essentially the same reason.
Of course, I’m also annoyed they replacement the awesome sounding and looking bloodstone with the much more tame aquamarine for March. Shows what I know about marketing.