I know this has been made before, that recast is 50% of the fast cast, i.e. 10% fast cast gives 5% recast. I recently finished my Marduk's Jubbah which says on wiki, to have 5% fast cast by itself.
I looked into testing just to see for myself, and when casting brd/whm with nothing but jubbah, my reraise recast was 57 seconds. Correct me if I'm wrong but, isn't 3 seconds a 5% recast reduction, meaning jubbah itself is 10% fast cast?
Without it casting reraise, it says recast 59. Perhaps it is just game lag and it's still just 5% fast cast?