Is Yang Gong's dragon ruler really useful?

I have thousands of young brothers all over the country, and I hereby announce:

The dragon hunting ruler is a complete scam. Since ancient times, no feng shui master has used a dragon hunting ruler to find dragons.

Dragon-hunting ruler, actually a divining staff, originated in England and was introduced to China in the last century.

Things that China has never seen have been popular for some time because those businessmen want to profit from them.