Ah. Yes it has indeed. In that last one David Chart said "The intent was that a magus could not cast a fast cast and a normal spell in the same round". However,that does not resolve the ambiguity problem as to the RAW as it stands, and in practice I think it's best for each troupe to decide what interpretation or house rules it prefers.
I'd suggest cleaning-up all of the Combat initiative rules.
- As an overarching super-rule - any character may take only one Major Action each round. No other rule trumps this; that's why it's a "super" rule. A major action includes making a melee or ranged attack, or casting a spell.
- Walking, speaking, and so on are Minor Actions; you may take minor actions in addition to major actions, within reason, and can do so out of your initiative turn. A shield grog guarding a maga, for example, often will walk around her during combat.
- Casting a Fast-Cast spell is a Minor Action; it is assumed to be sufficiently weak as to count as a "minor" thing. You can cast it off by making a Finesse roll against a fixed ease factor of 6 for the first one, 12 for the second one, and so on; a fixed EF is used because initiative order is cyclical, and to avoid the issue of wanting to have low initiative. You cannot combine fast-casting with any spell casting options, just as the RAW says, and this includes multicasting for fast-casting using spell mastery; minor actions are supposed to be minor, remember? You can fast cast whatever effect you want, whenever you want; restricting it to only reactions or defensive spells doesn't make sense.
- Activating a magic item is a Major Action, requiring Concentration just like spell casting. Triggers are never mechanical, so you cannot activate numerous items by using the same action, and different effects always require a separate trigger, so you cannot activate several effects with the same trigger. Environmental triggers react to major change in the magical environment, like changes in aura or time durations, just like the RAW says, not to physical changes like opening the bag. However, some effects will function on any available target (e.g. a Room effect), so affecting multiple targets with multiple items and/or effects or without taking a Major Action are all still possible.
- Casting a MuVi spell on a spell you are casting requires the MuVi spell to be cast first, have a Concentration duration, and to roll for Concentration for maintaining a spell (the MuVi spell) while casting another (the spell to be affected). Casting a MuVi spell while another spell is being cast by another magus requires coordination, or Fast-Casting, or casting and holding a Concentration-duration spell as above before the other magus has begun casting his spell.
Or something like that.
Yair