I don't believe that D: Sun effects flicker at sunrise/sunset. I had thought that D: Concentration effects did, if the item has a Concentration modifier, but rereading shows that I'm wrong. "Effects left to their own concentration start to wear off at sunset and sunrise. At these times, the wielder must concentrate for a few moments to perpetuate it until the next sunrise or sunset, whichever comes first." Which I don't like. It basically gives Concentration effects a de facto Sun duration, save that it doesn't take another Use to recast it.
Which, as I said, may work more or less for flaming swords, but not for MutoForm spells. If you allow a grog under Eyes of the Cat to still strike despite this, you're doing intelligent parma.
I'm sorry, I just don't understand what you mean.
Things that are fully magic => Does this mean Creo-ed things?
Things with magic that affect the one with MR => ??? You mean things that have non-creo effects on them and that are brought to the magus?
If so, your exemples are wrong.
The boulder exemple says that Mutoed items are resisted, not suppressed.
The flaming sword exemple says that the effect is suppressed, not resisted.
If you mean something else, I just don't understand what
It depends whether there are active effects or not on the talisman. If there is, can they penetrate?
The Aegis having to penetrate could have provided a partial solution. Alas...
So no, I'd say it doesn't...
Unless we rule that the Aegis doesn't affect magical effects that are under a Parma. Which could make sense.
OR
Unless we rule that Aegis/Parma/MR don't affect constant effects.
Which would solve this problem, and mean that a sword enchanted with a constant (sun duration, 2 uses/day, +3 constant) Edge of the Razor of Flaming Blade would not be resisted. Saying, in short, that constant effects are natural.
Which should work, mostly, as far as I see it. This changes the setting, though, making permanently enchanted weapons valuable and useful against both magi and magical creatures.
It also means that if you go through fire created by a constant effect, you get burned.
I seem to recall David Chart saying they used the RAW MR because, through numerous playtests, it was the one with the less bugs and problems.
On how many effects can you concentrate at once? 
Note that concentration duration with item maintains concentration are already about as hard as Sun duration effects anyway. This just saves you one use per day.
But that's the big advantage of constant effects: They don't flicker.
The original spells are R: Touch + D: Sun. This is R: Personal + constant (D: Sun, 2/day, environmental trigger).
It doesn't do much - I'll grant you that. It does clarify the effects of things like Wind of Mundane Silence on it - waves, not dispelled until the next sunrise/sunset. It makes MuVi enchantments 1 level lower. Regardless, there are published books and the official view agreeing that this is how it works.
Sorry, could have been clearer. Non-permanent Creo'd things. Fully Muto'd things (such as a magus in the form of a bear). There is no non-magical presence in these cases.
I don't see how that helps us. It's easy to figure out how Wind of Mundane Silence works on it, it dispels the effect until the next time it triggers. Are you arguing that this is a good idea because MuVi enchantments are too expensive?
It would be nice to have a quote. I can't follow what exactly you are arguing this official view is... that items with constant effects should be pushed out of a foreign Aegis? That they are permanently dispelled? Both of these seem like really dumb ideas to me, no offense intended.
I'm claiming the only consistent thing here is that the item "wave slightly" instead of having the constant effect end. That is consistent with the constant effect, the description of Wind of Mundane Silence, and with the guidelines to destroy enchantments.
The question had come up with Hermetic Projects and why the MuVi spell wouldn't be 2/day to fire off each time the spell it's affecting occurs. As you can see, the official view is it's one single effect, not one that is actually recast twice per day.
I agree that both ideas seem really dumb. But if a constant is resisted, how is it resisted without using one of these options? To avoid this, I would argue it should not be resisted by the Aegis, and if the Aegis doesn't resist it then I don't see that Parma Magica would since the Aegis covers even more than Parma Magica. The heavily implied situation that Hugh of Flambeau's item's unbreakable enchantment doesn't seem to cause the item to be resisted would be consistent with what I'm arguing. Also, this would make longevity rituals continue functioning when entering a foreign Aegis and allow those under longevity rituals to punch each other without being blocked by Parma Magica.
It sounds like you're saying that when an effect with D:Sun is hit with Wind of Mundane Silence, sometimes it doesn't get dispelled, depending on whether it was cast by an item instead of by a magus.
Why not just require the MuVi spell to be constant as well? Is this all David said on the matter?
If a constant effect is resisted by an Aegis, it just doesn't trigger, just as a spell cast by a magus doesn't manifest. That really seems the simplest solution to me, and I still don't understand why it would be interpreted differently. It is clear from the description of a constant effect that it is a D:Sun effect that is triggered twice a day, and not a single effect that lasts forever.
I'm afraid I can't agree. The item has a magical effect on it, it is clearly magical as far as Magic Resistance goes, just like Edge of the Razor. 
No, I'm claiming a constant effect is not a D:Sun effect. It is only calculated using D:Sun. I'm saying a constant effect would not drop while D:Sun effect would drop.
Because this is entirely inconsistent with how MuVi works. The MuVi spell must last the duration of the casting of the effect it is altering, not the duration of the effect it is altering.
That's how I misread it, too. But that is not the case. The effect is constant and triggered only once. What you are reading is a description of how to calculate the effect level and modified effect level of a constant effect.
So why is Hugh's weapon able to penetrate against a magic resistance of 10 with only 0 penetration on the constant, R: Personal, indestructible effect? I would assume you would also say a magus under the effects of a longevity ritual cannot punch a magus protected by Parma Magica since the magus has a magical effect on him/her. But if the magus transforms into a magical being, wouldn't this also be a magical effect, and even more so than the longevity ritual? Yet in the latter case by RAW such a magical magus could punch through magic resistance.
But this is ludicrous. It's a magical effect, so it must have a duration. What is the duration? There is no such thing as Duration: Constant.
All right, then why not trigger the MuVi spell each sunrise and sunset? Why create a new sort of duration that only applies to effects cast by items? I take it David didn't elaborate.
I would say it can't. Whoever wrote Hugh should have come up with a better way to make an indestructible axe. For example, a CrTe D:Mom effect that repairs any damage it takes, triggered every moment, with unlimited uses per day. It could thus be damaged inside a foreign Aegis, but that's the risk he takes.
Yes. I think it's dumb, but it is at least consistent and simple. I would support the idea that a Longevity Ritual is special and doesn't have this side effect, but any active magical effect that targets a magus should make his body resisted by the Parma.
How does the magus transform? If you mean he casts a MuCo effect on himself, I would argue he can't punch through Magic Resistance. If he somehow becomes a being with Magic Might, he doesn't have a magical effect on him, his essential nature has changed.
Callen: IIRC, magical transformation and LR are not active effects. Your new you is natural, just like a magical creature claws. This is not a sustained effect, it can't be dispelled, which is the difference.
OTOH, if you're under Endurance of the berserkers, you are magical, and thus resisted.
So, if I understand:
Creo effects are resisted, as are Muto effects with target greater that Part (only the part is resisted, so a variant of Eyes of the Cat with T: Part means you can still punch a magus)
The rest are suppressed.
So:
- A flaming sword is resisted, and is an invisible blade
- Acid mutoed into water is resisted, as is the reverse
- A boulder propelled by magic (a la crystal dart) has his "propelling force" suppressed.
IMO? The distinction is clear enough that this is adjudicable (which is VERY important), but, as the effects that people usually want supressed/dispelled are the ones that are resisted here, it's useless to go with this.
We can reverse things, which works fine for the Fire and Invisible blade, but means that you would dispell a bridge you'd fall upon :-/
This is why I went with dispell for weak spells, resist for the rest.
But yeah, there is no perfect solution 
That's how I took it, for effects who are cast.
The question remains for permanently enchanted effects, like Callen's armor.
There's a guideline that says "Dispel a Hermetic enchantment with a level less than the guideline used + a stress die (must be ritual)".
IMO, it means it disenchants your item, so that it permanently loses the targeted power.
I think callen means that Constant effects can only be targeted by this. I'm not sure he is right, although he may be. I just don't know. I don't think this is bad, though.
If using this, an armor that casts Hardness of Adamantine twice per day would be dispelled by a WomS. An armor with a constant HoA would only have it cease working for the round in which it is hit by the Wind.
This doesn't solve the Aegis problem, though.
Doesn't anyone want to comment about my proposal that Constant effects are considered as Natural?
- It means that enchanted swords are better than non enchanted swords.
- It means that items like callen's armor can be brought into an aegis without problem.
- You can still disenchant them, though.
This conversation has just ZOOMED into deep MR philosophy. But I am pretty sure you guys have it under control. Better to have this discussion now rather than let it bog down play later.
two things...
I have no idea who Hugh is
and
Constant Duration is an abbreviation I have used before (though I think not ever here). As long as the numbers crunch (do note these), I don't mind if the main entry reads D: Constant as a point of clarification.
Example...
TeFo19 Enchantment
R: Personal, D: Constant, T: Ind
(Base 5, +2m Sun, +3L Environmental Trigger, +1L twice per day)
This affects the item only, so I also don't mind listing it as R: Item. As long as the notes fit regular standard.
The above enchantment makes the item subject to MR. The item can be brought into an Aegis, but the effect is null unless it was A). fabricated within the area of the Aegis since it was last cast, or B). the weilder/operater was part of said casting or has a token.
To be really clear, my actual position is, "This pink dot is such a huge pain in the ass that I tend to just throw spells at them."
Examples like this, where I try to make a simple distinction and it turns out to be somebody's major argument, is exactly why I just avoid the pink dot altogether and go for direct-effect magics (or avoid combat casting altogether). On the other hand, I understand that other people want to play in a world with magic swords and invisible opponents and so we should have some general guidelines for them to work with.
Edit: I change my vote to "As RAW, and we respond to attempts to get anywhere close to these semantics with threats to sidetrack the game with an in-depth discussion about whether or not using MuCo spells to affect penis length have any bearing on the validity of a player's argument."
RAW disagrees with this in numerous instances.
That's exactly what I thought. David Chart's comment was very specifically aimed at this to say it is not the right interpretation.
Yes this quite specifically violates the mechanics. That would require a ritual effect firing off an unlimited number of times from an item. First you'll have to get the ritual in the item. I'm not aware of any way to manage this and have it work repeatedly. And then you have to deal with the very questionable validity of such a trigger.
CrTe, D:Mom, Environmental trigger: when object is damaged. Unlimited uses. Make it powerful enough to essentially create a whole new item if need be.
I still have no idea who Hugh is.
Anyway, I think Mercuria just forgot about the ritual limit. And there is a mystery route out there I am sure.
But I thought of a better way 
A high level Creo ritual that actually improves the metal to that state, rather than muto-ing it. But I suspect that was not the way they wanted to go creatively.
A longevity ritual is either explicitly or absolutely implicitly an active magical effect because it causes Warping. I'd have to search carefully to see if it's explicit.
You would say the same about a familiar - it not being a sustained effect, right? In this case there is no Warping, so that would stand up better. Yet in this case it can be explicitly dispelled, so why couldn't a longevity ritual?
I'm still considering it. I think it has a lot of promise to it.
It's still a ritual.
Can you quote me the description of Duration: Constant? I fail to find it anywhere in my core rulebook, and I don't see it mentioned in the errata, either. Is this something that was added later? Where?
Why do you think this needs to be a Ritual effect? There's an item in Broken Covenant of Calebais that does this very same thing.