Well. I'm looking into making a Mystic Theurge, and while he probably wont learn alot of Cleric spells (since my Wizard level will be 7 for 9th circle spells) he's not going to have many at Caster Level 13... But when my Theurge make's 10 (I'd do it at 5 if the game had stats for more than five levels...) will my caster level be 20 (all levels added up) or 30 from the technical caster level of 17 for my Wizard and 13 for my Cleric? Help please because this is a deal breaker for me... I can't find anything saying that it can't be done in the Core Rulebook.