Spell Block Not Reporting Overcapped Value

https://imgur.com/a/600w8wL

Spell block does indicate overcapped value on the character information screen. In the linked images I have at least 75% spell block before I allocated the small 4% chance to block spell damage while holding a shield, and that number doesn't change after I allocate the passive. (I am wearing a shield.)

By removing various nodes it seems that I should be at 76% chance to block spell damage without the Shield Spell Block small passive allocated, and 84% chance to block spell damage with it allocated. With every other stat indicating an overcapped value, it seems like Spell Block is supposed to as well.