Level 50 mage, 52 base luck, 56 with equips. Tried to equip blue goldwind shoes (lvl 50, 53 luk req.) Couldn't, said stats were too low. Levelled to 51, added in 1 more luk (base of 53), bang,equipped.
it could be that the item you are taking off has more luk then by 1 or so stats compared to the new item you are trying to equip, therefor say u hat 5 luk oa, but tried equiping a 4 luk.. something along the lines of that
Gave me 2 luk iirc, had 54 (52 base, 2 from hat for 54). I did check whether that was the case or not Miko. I was confuzzled.