In my world, magical aging would inflict the worst of both worlds: you'd have physical penalties because of your degraded body, without the mental benefits of long life.
IMO, the increase of mental stats comes from the experience and learning you gather over the years. Your brain stays the same-- or maybe even slows down a little-- but you're effectively smarter because you've "been around the block." If magic causes you to age suddenly, you won't gain that experience, so your mental stats will stay the same.
Physical stats still go down because you're walking around inside an aged body, with hardened arteries and degraded eyesight and lessened muscular capacity. You could treat it as if you'd been Magic Jarred into a body that looks like yours, but simply doesn't function as well.
IMO, the increase of mental stats comes from the experience and learning you gather over the years. Your brain stays the same-- or maybe even slows down a little-- but you're effectively smarter because you've "been around the block." If magic causes you to age suddenly, you won't gain that experience, so your mental stats will stay the same.
Physical stats still go down because you're walking around inside an aged body, with hardened arteries and degraded eyesight and lessened muscular capacity. You could treat it as if you'd been Magic Jarred into a body that looks like yours, but simply doesn't function as well.
