I managed to finagle my Empress equipment on without enough dex to equip it.
The catch? It's only one piece of the Empress set. And my total dex isn't enough to equip it without including its own stats...
Figures: 162 dex, +18% dex (15% all, plus the 3% dex on the axe) = 191.16 dex.
But, if you think about it - that means that without the Battle Axe, my stats are
142 dex, +15% dex = 163 dex.
Even including the 3% dex,
142 dex, +18% dex = 167.56 dex.
The only conclusion left is that the %stats potentials, applied to the Battle Axe's 20 dex, are allowed to be included in the total.
So it's certainly checking whether the item can be equipped by doing
191 (total) - 20 (equip) = 171 > 170.
Just thought it was interesting how potential can abuse stat requirements. And that I can only do this because of the 3% dex on the weapon itself; if I recube it I can't wear it. (since 162*1.15 = 186.3 dex, which would come to 166 without the weapon's stats)