Read the description of spell speed on your character, it is not a useless stat, jut not #1 stat for Red Mage.
Issue being for those of us who do play blm and Red and must use the same gear... Blm Spell Speed is number one, Red Mage i would think it is 3rd stat or possibly second after Crit (though i think DH is better after Crit then SS)
There simply has just not been enough content and testing yet to warrant if one stat may not be all that useful.