They are DEX-5 MND+5, it's a way to get more stats so I'll be able to 5/10/15 more STR on LNC than w/o them. As they are kinda reversed for mage/melee, I think SE's line of thinking was that they'll help you play opposite disciplines w/o having to reallocate everything.
They are good because of the increasing stat cost as you go up as well, and that stuff like int/pie is mostly useless on the DoW so losing 5 or 10 points doesn't affect anything.
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