I have a character that hadn't yet eaten 120s in swords and tactics. Yesterday evening I ate both scrolls. Following my own advice, I went into a dungeon to raise my skills. I've been killing gold elems in BT. Swords went from 105 to 120 in the same time that tactics went from 110 to 117. This strikes me as odd, given that they're getting used at the same rate. Maybe the fact that swords is difficulty based and tactics is simply use based makes the difference?