Dannyalcatraz said:IOW- its not how the Feat was originally designed. They decided afterwards that the Feat as written would cause a significant power imbalance between the magic system and the psionics system...
It is how the feat was originally designed. You are reading into every sentence (both in RAW and by Cust Serv) things that are not there.
If it were originally designed as allowing spells outside the spell list, it would state it with something like: Normal: spells cannot be chosen off the caster's normal spell list.
As for balance, Psions get about 170 powers to choose from and Expanded Knowledge gives them about another 100+, many discipline ones for which Sorcerers already get equivalent spells. That feat was designed with those fewer number of powers in mind.
Sorcerers already get well over 600 spells to choose from (all WotC sources, ~350 spells in the PHB alone). Allowing them to choose from another 1000+ spells which they are denied for specific balance reasons is way out of balance.
I think you do not quite get the concept of balance in this regard. It refers to spell synergy, not just the ability to have a specific spell.
For example, Polymorphing into a specific creature might be balanced. However, following that up by changing into a Colossal form of that creature with a Wu Jen spell might suddenly be very unbalanced.
The more spells suddenly opened up for use, the more spell synergy possibilities that are created. The Psionic ones are controlled. From 3E to 3.5, certain feats / powers were modified / removed to get rid of certain synergies in the Psionic system. This cannot be done when you open up all spells for Arcane casters.
And, these synergies can be controlled with certain PrCs like Mystic Theurge since the caster is at least 3 levels lower (4 for a Sorcerer) with his spells in each class. This does not happen with your interpretation of this feat.
Opening up all spells for an Arcane caster is VERY unbalanced.