Enchanting: Rods inherit not functional

db_structure: 21_16_037
 

There is a problem with enchanting rods. Each major craftable rod should  "inherit" the possibilities of lesser ones. That gives an opportunity to have only 1 rod in inventory (with you) not causing shortage of bag space.
This rods ability is stated in description flavor text. 
But for now it is broken. For an opportunity to chant something lesser levels you should have whole collection of chanting rods with you. 
I attached the vid to demonstrate the  behaviour.