How does Learned Sorcery work?

[gadren]

One of my players wants to take the Learned Sorcery (http://www.d20pfsrd.com/classes/core-classes/sorcerer/archetypes/4-winds-fantasy-gaming---sorcerer-archetypes/learned-sorcery) archetype for his sorcerer.

I'm leaning toward allowing it, though I'm honestly not sure if I'm interpreting it correctly, and was curious how you guys read it?

I read it as: you can prepare one spell of each spell level (up to the max level you can cast as a sorcerer) from a spellbook as if you were a wizard. This is tracked in addition to and separately from your normal sorcerer spells. You give up pretty much all benefits of a bloodline in exchange for these wizard spells.

[Sagetim]

Well, the sorcerer still gets the bonus class skill from a bloodline, and all of your casting is still charisma based, but yeah, it looks like that archetype drops all sorcerer powers, feats, bonus spells, and arcana in exchange for the ability to prep one spell per day from a spellbook.

The way it is described, I would interpret it as the following example: Sorcerer Bob has learned sorcery, so as a level 6 sorcerer he has gained 4 extra spells known (one cantrip, one 1st, one 2nd, and one 3rd). These bonus spells are contained in a spellbook, and because he can choose and prepare spells like a wizard, I would interpret that to mean that sorcerer bob can add spells to his spell book like a wizard can (from scrolls, copying, or what have you). However, he can still only prepare up to one spell of each level from his spellbook, the rest of his slots are spontaneous casting from his normal spells known.

[Pex]

It's rather weak. The character gives up all bloodline abilities just for the privilege of choosing what his bonus spells are instead of the set in stone ones given by the bloodline, and he needs a spellbook to do it. I would advise against doing it. He's gimping himself.

[gadren]

It's rather weak. The character gives up all bloodline abilities just for the privilege of choosing what his bonus spells are instead of the set in stone ones given by the bloodline, and he needs a spellbook to do it. I would advise against doing it. He's gimping himself.
I think he'll be alright power-wise. I just wanted to see if I'm interpreting the archetype correctly.
Every other choice of his is pretty optimal, this just fits his character concept (Sorcerer raised by a wizard who tried to train him as a wizard).
Plus, there's a loss in power but a gain in versatility, since he can change what spells he puts in the those prepared slots each day.