Me too. Before I had come across the topic in question, I had never even thought it an issue. But apparently it is.
When I read the topic I mentioned in my first post, I went searching for previous topics and found some on the Aegis/Penetration and on the Wizard's Communion.
Posters were talking about using Wizard's Communion on Aegis of the Hearth to gain extra Penetration, and I could not determine why. I still can't.
Adding to my previous issues with Wizard's Communion:
atlas-games.com/arm5/arm5errata.php
"Muto Vim (p. 159): Add the following paragraph to the end of the general description: "A Muto Vim spell, like any other Muto spell, can only change its target for as long as the Muto Vim spell is in effect. Thus, its duration should normally be at least as long as the spell that is its target. The spells below have a duration of Momentary, but versions with longer Durations can be invented as normal."
Even assuming a complete re-write* to the canon Wizard's Communion to allow it to affect Penetration (it can't at all as it stands), the canon version also has a duration of momentary. Anything it did to the year-long Aegis of the Hearth would cease, at best, a few seconds after Wizard's Communion was cast. A version with a duration of year would have to be a ritual itself. So, if you want to cast a Aegis of the Hearth 30, you need a minimum of 60 levels of Wizard's Communion Ritual learned by the participating casters, so I am going to hazard a guess that this requires six pawns of Creo/Vim vis and another twelve pawns of Muto/Vim vis. Each covenant's annual protection festival just got a lot more expensive.
The inability of Wizard's Communion to have any effect on Penetration (and a general overall uselessness) appears clear to me, and so I was thinking there might be some other rules I had missed. Which is why I had posted this topic.
As far as Aegis of the Hearth's effects needing to penetrate, I'm personally against the idea. As far as I am concerned, requiring it rips out half the value of the Aegis, but that's another issue. I have been working ideas on both sides of the issue for days and still haven't come up with anything I really like, and is why I haven't posted anything else, much as I wish to lead a knee-jerk crusade against Penetration in this case.
- This is what I have on a re-write to Wizard's Communion so far:
Muto Vim General Wizards Communion
Range: Voice, Duration: Variable, Target: Individual (Ritual)
A special product of a pair of researchers from House Bonisagus and House Guernicus, Wizard's Communion has spread throughout the Order of Hermes. It is part Hermetic Magic and part Mercurian ritual. It was the result of a Hermetic Breakthrough that many felt was Major, but was ruled Minor by Notatus, the Primus of House Bonisagus at the time. It has effects that are not strictly bound by the standard spell guidelines. The primary effect of the breakthrough comes in the chameleon nature of the spell's attributes. The duration of Wizard's Communion is the duration of the spell it is targeting, and if the target spell is a ritual, so is Wizard's Communion. The lab texts of the research were published, but due to the effects of both authors writing portions of it in completely different styles with less than perfect clarity and contradictory statements, no one has been able to duplicate the breakthrough, or even use it to further their own research.
Wizards Communion functions as an enhancement of Wizard's Boost, it targets another Hermetic Magic spell, and increases its power. A group of magi assemble with one as a leader and the others as followers. The maximum number of followers is equal to the leader's Magic Theory score. All participants must know Wizard's Communion. The combined level at which all participants know Wizard's Communion must be double the level of the spell to be targeted, or Wizard's Communion cannot be cast. The leader must personally know the spell to be targeted, and will be the one who casts that spell. All participants must cast Wizard's Communion successfully. The leader must make the standard concentration roll for casting a Muto Vim spell at the same time as another spell: Intelligence + Concentration at 9+. If the spell to be targeted is itself a ritual, then the leader must decide if each follower is also a part of that ritual (important for Aegis of the Hearth). If Wizards Communion is a ritual, then because there are two rituals underway at once, all participants must also make a Stamina + Concentration roll with an Ease Factor equal to the magnitude of the spell to be targeted (divided by ten + 2).
Every two followers, or fraction thereof, casting Wizard's Communion adds one botch dice to any botch rolled for all participants. This value is fixed once Wizard's Communion commences. If any followers drop out of the ritual, the extra botch dice total does not change.
If any spellcasting or concentration roll on the leader's part botches, the entire operation fails and all vis used is lost. If any follower botches a casting or concentration roll, they are removed from the spellcasting operation and the final bonus provided is reduced by that spellcaster's absence. For each follower dropped from the ritual, the leader must make another concentration roll of Intelligence + Concentration at 9+.
For every follower casting Wizard's Communion, a bonus of five levels will be provided to the spell that is targeted. The troupe may make recommendations about how they want the bonus to take effect, but the storyguide makes all decisions (just as in Wizard's Boost). The most common effect is to increase the casting total of the spell beyond what the leader rolls for the purposes of enhancing Penetration. Less common effects including boosting range and duration. The least common effect would be to boost the target. The descriptive effects of the spell, or other factors, are never boosted.
If vis is used to boost the power of Wizard's communion, that amount is used to increase the bonus for the spell to be targeted noted above. Each follower may independently contribute vis for boosting, although if every participant did this at maximum, it would become expensive. If the spell to be targeted is a ritual, then the leader must pay that spell's vis cost and cannot contribute to vis boosting on Wizard's Communion or paying its ritual vis cost. If Wizard's Communion is a ritual, the followers must pay its vis cost (limiting capacity for vis boosting).
For reasons unknown, Wizard's Communion cannot be mastered. [I am thinking of having this type of restriction on all the classic part-Mercurian Hermetic spells, primarily to avoid the Spell Mastery on Aegis of the Hearth with Magic Resistance option trick for easily getting around an Aegis; assuming Penetration is being used.]
While the above makes Wizard's Communion useful, it is also pretty complicated and alters vis economies for covenants. All just to get it to be able to add Penetration to Aegis of the Hearth so this standard defense spell can have a hope of functioning as written. Hmmm. Some further thinking is required here.