Cool thanks CJ. This definitely applies to me
So, I just spotted evidence from way back when, before HoH:TL iirc (GotF before HoH:TL, right?), confirming there was only a single Mastery Ability for all levels of a General Spell. Take a look at Philippus Niger on p.60-61 of GotF. He's got a whole bunch of General Spells known at multiple levels, in each case with a shared Mastery Ability. I guess those should all go into the errata now.
Both note their first printing as April 2005.
ISBN of GotF is 1-58978-072-8, of HoH:TL is 1-58978-074-4 - but these are traces of administrative processes, not of writing or editing. The same holds for the numbers in the product line: GotF's is AG0276, HoH:TL's AG0277.
The books have no author in common - though the authors did playtest each others' books. So by lack of fine-tuning they can very easily contradict each other in details like character stats, without there being any arguments of precedence. They have the editor in common, or course.
GotF was developed in parallel with ArM5. There are a number of points where details do not quite match, and that is one of them.
Oh, I get that things don't match. That was what I originally brought up about Adaptive Casting way back when: that it contradicted itself. I'm just pointing out that this side of the argument existed in more than just the reading of the core book and the contradiction within Adaptive Casting. It had actually been written into a character in a book way back at the very beginning. So taking the opposing stance on General Spells means write-up is now incorrect and so should be included in the errata now.
Just found the new version of Adaptive Casting in the Definitive Edition manuscript and have one question (which theoretically also applies to the old wording): Does Adaptive Casting allow Spell Masteries to be applied to spontaneously cast similar spells?
No. Masteries are for Formulaic Spells only.