[Sir Mandorallen]

NEVER FEAR!!!!! BLACK_KNIGHT IS HERE!!!!

I shall give you an elongated description.

*takes deep breath*

When you dual class as say, a level 9 mage to a fighter, you temeraraly (sp) lose the ablities of the mage. That means no spells. Then your character acts as a level one fighter. (cause thats what he is dualing to) You then gain XP and levels in only the fighter class. When your fighter reaches the level of the privious class, (in this case 9) you get back your ablities from your mage, but you don't level up as a mage any more. Only as a fighter.
So that means that you have all of the spells and abilities you had before you leveled up but they can never increase to something better. The increases instead go to the other class.

*lets out breath forcefully*

There.... hope that helped!