Mana pool, int vs mana items sanity check

[maultar]

People tell me once above 200 int int items are only 5 mana an int. Using the original UI, I can see mana displayed as a finite number. Unbuffed I have 3027 and 223 int. I remove a 5 int earring my mana pool goes down to 2991. I put the earring back on and remove a 35 mana bracelet it goes down to 2992. With that logic I should be able to replace the 35 mana bracelet with a 5 int bracer and have 1 more mana. Nope its now 3014. How can that be based on the numbers above?

Throw a wrench in to that finding, I then replace a 5 int earrign with a 35 mana black saph earring, should be more mana pool right? Nope, it goes down to 2992 like I thought the initial test would have done with the bracelets. Does int vs mana varry per slot? Is there a coding problem with specific items? Is the original UI just gimp? What will happen to Sookie now that her best friend is dead?