Apprentice feat on a beguiler ?

[Bobur]

So the feat: Apprentice DMG2
Lv1 only

Originally for a flavor I was thinking to use this feat on a beguiler build, but I am not exactly sure how this would work on him.

Spellcaster +2 competence on Spellcraft checks; Arcane caster: one additional spell known at 1st level, beyond 1st Prepared casters can learn spells from Mentor's spellbook at no cost, Spontaneous can learn a new spell in place of one already known; Divine caster: choose a preferred spell that can spontaneously be cast in a similar manner to good clerics and cure spells Knowledge (any one) Use Magic Device

Can I do this just once or is is otherwise limited ? I would guess, that I could either replace 1 spell on a level up, somewhat like maneuver from a Crusader/Warblade. OR I have to return to my master to replace one spell and learn a new one.

Which would be extremely useful for a beguiler if it actually worked.

[Pilo]

Casters have to pick spell known from their spell list if not stated otherwise. As beguilers know their full spell list, it will be useless.

[Bobur]

Iexpected some kind of hook on this.. would have been too good.

[Ellrin]

Even RAI, there's no real way to make it work for a beguiler, since the three possible categories are prepared caster that researches spells on its spell list; prepared caster that knows all spells on its spell list; and spontaneous caster that learns a given number of spells from its spell list; where beguiler is spontaneous caster that knows all spells on its spell list. For the most part, if you don't fit into the learning/casting mould of wizard, sorcerer, or cleric, you're out of luck with the spellcaster version of that feat.

Now if I were a very permissive DM (I'm not), I'd say you could use it for Sha'ir. RAW, I think it works with the divine caster version (though that's weird and probably OP considering how Sha'irs normally prepare). RAI, because Sha'irs learn spells like a sorcerer, you could also say it works for the spontaneous casters version, even though they aren't spontaneous casters.

The best/worst part of it all is that there seems to be no provision in the description that prevents a class that can use multiple versions of the spellcaster benefits from using all versions that it can. So you could conceivably, if both above uses were approved, use both--so you can retrain one spell every level, and choose a preferred spell to spontaneously cast instead of waiting for the gen on top of the normal benefits.

...so that, frig.

[Bobur]

Another thing I thought of:

The character was raised in a cloister, but then decided to jump out for the city, giving 1 Lv in cloistered cleric.

Cleric into beguiler would somewhat screw up the skill set up so it might as well be turned around.
Beguiler > c. cleric1 > beguiler

1 Question: The spells added to class spells : Do I have to keep them sep. from the beguiler list or are they all thrown together ?
DO I get only the 0 Lv spell for 1 Lv of c. cleric ?

- 2nd: When picking the 2 domains, do they have to be on MY deitys list ? I wanted to pick Shar as a goddess, but she doesnt offer tyranny or domiantion. (which would buff the spell DC of enchantmens pretty much)

While I am at it:

3: Runestaff + beguiler ?
Does a runestaff add the spells to my spells known or do I cast a spell and replace it with a fitting one from the staff? Can I do this as often as I want or only a limited number of times ? Im confused about how a staff interacts with the special situation of a beguiler.