Spontaneous Casting Oddities

[NoACWarrior]

Hey everyone. I was looking at the spontaneous casting class features (ability to swap prepared spells) for multiple spell casting classes and noticed that the wording doesn't say you are restricted to spells of that class. I know its a silly RAW interpretation to apply spontaneous casting to non-spontaneous casting classes that the caster has, but does anyone else get the same vibe as me for this odd wording in the class feature?

What I'm looking at is being a wizard with prepared spells, and then having at least 1 level in cleric which gives you spontaneous cure or inflict. Also, the wizard/cleric has the healing domain unlocked via use of arcane disciple (if the healing spell you want to spontaneously cast ISN'T on your spell list for the class you are ditching a prepared slot on and casting the cure of inflict it DOESN'T work). The resulting outcome would be "sacrifice a wizard spell to spontaneously cast a cure / inflict / summon / domain spell of the same or equal level" which gives prepared arcane casters a significant boost in power when multiclassing with druid/cleric or taking the spontaneous casting feats.

I understand that the RAI is probably "only works on class provided spells", but I'd like a RAW discussion at this time.

[NoACWarrior]

Forgot to add the Spontaneous Healer and Spontaneous Summoner feats - as a wizard with arcane disciple you add these spells to your class list.

But it breaks my mind that something like this is possible.

[nedz]

Arcane Disciple
These options are best for the fixed list casters (Beguiler, Warmage, etc.) because they know their entire list.
These options are next best for the prepared casters (Wizard etc.) since they can just prepare them almost as normal.
These options are worst for the Spontaneous casters (Sorcerer etc.) since they must still consume a spell known to learn them.

Spontaneous Healer and Spontaneous Summoner are a bit more open.

As to your point about swapping out spells, well that's just another version of the controversial text in the PH

Spells

A sorcerer casts arcane spells which are drawn primarily from the sorcerer/wizard spell list.

Talk to your DM is the usual advice here.