I was going to post this in bugs but not even sure if it is a bug.

Critical displays and changes on the character screen once you upgrade it.

Armor Passive and also Damage Passive do not show on chracter screen nor do they change the base damage or bonus damage if you respec and put nothing in the main stat.

I just tested it on a mage respec'd and the base damage was 1.5 put 5 in damage and nothing changed.