Not sure if this is new from patch 5.0, or if it's been there for a while, but when you equip an item/are affected by spells that change saving throws, your saving throws don't actually change in the character sheet (nor in the character sheets hovertip, though the breakdown on the hovertip does reflect the new/removed entry affecting the saving throw, however it no longer adds up, as the "result" didn't change. This appears to be corrected after a save/load cycle, however.
E.g. loading save w/ safeguard shield equipped, saving throw bonus breakdown hovertip reads:
+5 to Saving Throws
+4 from Proficiency
+1 from Safeguard Shield
Unequip it, and you just see:
+5 to Saving Throws
+4 from Proficiency
From quick test of casting grease spell, it does seem to use the correct numbers, as it apparently gives the individual breakdown of contributions, and not the (incorrect) precalculated total. So this appears to only be a cosmetic issue.