One TKD school uses an independent series of poomse, the Chung Bong series, which were developed by one man in 1974. (41) -mattJ

The, "One TKD school", is actually quite a few, mostly found in the Midwest where the developer first moved directly from Korea.
The developer is Jay Hyon.
Chung Bong forms actually developed 1966. Perhaps first performed in Korea in 1974, though not confirmed.

Many students of grand master Hyon opened their own schools and are still preforming and continuing to teach these forms.

These can be seen here in video and pdf format as demonstrated by Karate North (under Master Tom Sullivan):

Think good, and it will be good.