But under several monsters before the new stat block, 'spellcasting' is the SA. It was not divided up by each spell
Umm. No.
A. Arcane & Divine Talent don't have a Save DC, you cannot take Ability Focus for them.
B. Instead of quoting GitP hearsay trash that's proven to be as accurate as zook1shoe, you could have taken the minute to read MMV's section on reading the entries which separates Spellcasting from Special Attacks & Qualities. Which is further demonstrated by several creature entries that obtained real Class levels, such as the Hobgoblin Duskblade a whole two pages before a Hobgoblin with Arcane Talent. Or even the Spells section in the MMv's Glossary. You know, just about anywhere in that book rather than posted hearsay shit.
C. Lastly, MMV & FCII's new Talent thing is creature specific rules. They don't appear in the MMV's glossary, headers, or descriptors. They do not note they are an update or change things retro activity. So while Polymorph/Shapechange can, and
only can, be used to turn into those specific creatures to obtain the key Talent ability. There is no foundation to claim Polymorph can let you obtain a Solar's Spellcasting or anything of the like without houserules. And claiming Spellcasting in Ex is a fundamental failure on your part worthy of total ostracization as you have fully and whole heatedly proven your inability & lazyness to preform proper research into a topic while simultaneously showcasing your creative imagination to fabricate your desired results without any regard to what is real or not.