1. Launch his charge specials without charging.
2. Cancel one special into another, or into and out of his command attacks. For his d,u+K, you can cancel it into his

3. Have multiple fireballs on-screen at a time.
It does have some limitations.
1. You do less damage, and can't build stock.
2. You can't perform a DM for free, unlike in XI, although if I remember right using a DM will end the mode.
3. You can't dizzy someone with it.
4. You can't cancel a whiffed move.