A little off topic from OP, but since the conversation has turned to cross-class abilities I'll share my observations. There are 4 factors involved in spell casting you need to consider; Cast time, recast time, spell duration and spell effectiveness. In regards to the first three the formula is simple, without affinity you receive a 20% penalty, with affinity you receive only a 10% penalty. For example, Emulate has a 1 minute recast timer, and effect duration of 30 seconds. Without affinity on another class this becomes 72 seconds and 24 seconds respectively, with, 66 seconds and 27 seconds respectively. -n regards to spell effectiveness there are an additional 2 factors that can effect this penalty on top of the base 20%/10% penalty. For all spells, you have to meet the recommended rank as listed in the spell description, and with some spells your attributes play a role in effectiveness ;as well (think cure where both mind and magic potency effect the level of HP recovered.)Spells not effected by attributes like siphon TP will follow the 20%/10% penalty as long as you meet the minimum rank requirement. All of this is regardless of whether you are playing as a discipline of war or magic. With weaponskills you also need to factor in damage type of the weapon being used, ie skull sunder is a slashing attack so it won't be as effective with a piercing or blunt weapon.