Cheesy Gestalt Build: Would it work?

[Arkanist]

Although this may sound like a redundancy, this build is a doozy if it works. You see, this (hypothetical) build assumes you allow multiclassing in gestalt. So a fighter1/wizard 1//cleric 2 would count as a gestalt wizard and cleric 1, and a gestalt fighter//cleric 1 with cleric levels stacking with the level of cleric//wizard. Under these gestalt multiclassing rules, would it be possible to level a gestalt archivist//wizard to 3, multi class to get archivist 4//wizard 3/ Mystic Theurge 1 and continue to level, getting +2 divine spell casting for each level you take?

Wrote this on my tablet, so the formatting may be off, but hopefully you will be able to answer this hypothetical build question.

[eggs]

This is why the gestalt rules say no to dual-progression classes.

EDIT: And before something like Rogue/Loremaster//Wizard comes up, it's also why classes that advance the same feature do so at the fastest progression.

[JustPlayItLoud]

From the SRD, with the relevant details bolded:

A gestalt character can’t combine two prestige classes at any level, although it’s okay to combine a prestige class and a regular class. Prestige classes that are essentially class combinations-such as the arcane trickster, mystic theurge, and eldritch knight-should be prohibited if you’re using gestalt classes, because they unduly complicate the game balance of what’s already a high-powered variant. Because it’s possible for gestalt characters to qualify for prestige classes earlier than normal, the game master is entirely justified in toughening the prerequisites of a prestige class so it’s available only after 5th level, even for gestalt characters.

[Pilo]

No, first: theurges classes are subject to GM advisal before being allowed.

Second: "Class features that two classes share (such as uncanny dodge) accrue at the rate of the faster class."

Archivist divine spellcasting is affected by this rule, and the faster it progresses is +1CL by level, so your character only progress of 1 level in archivist spellcasting.

If not, you could have done this : Specialist Wizard 4// Archivist 3/Focused Specialist 1 to cast Level 3 spell at an ECL of 4.

[Arkanist]

Thank you for satisfying my curiosity. I should have checked the srd first.