Every sign is ruled by a planet. The ruling planet is called the lord of the sign. If you look carefully you will find a symmetry axis that you can use to commit this information easier to memory. Check this short video where this symmetry is being visualized.
Visualizing the natural relationships between grahas in a graphic makes it possible to come to interesting conclusions.
Instead of debating about astrology techniques the astrologer must focus on his ethical and spiritual service to the society.