Parma Magica (would that be an adjusted 3?)

I'm not sure how to read the rules for Parma Magica. Page 85 says

While a magus is protecting others, his effective Parma Magica score is reduced by 3 points, both for himself and for the other people he is protecting. If the magus has a Parma Magica score of 3 or lower, his Parma Magica provides each character including himself, with a Magic Resistance of 0.

Should I take this to mean that if his score is reduced to 3 or lower (say, from 5 or 6) his Parma Magica provides each character including himself, with a Magic Resistance of 0? Or if his original score is 3 (or lower and then reduced by 3 to 0) his Parma Magica provides each character including himself, with a Magic Resistance of 0?

The rules then say

In the magus's case, this is added to his Form resistance, and a magus protected by another magus's Parma Magica may also add *his Form resistance.

(*his meaning the magus casting Parma Magica or the one being aided by it?)

If the adjusted score is 0, and all magi have Parma Magica of at least 1 why would a magus aid another magus, if the one being helped is better off casting it on himself instead?

Clearly I'm confused. This is what I love about trying to learn a new game system at 4 o'clock in the morning.

Thanks. Time for another cup of coffee.

I believe it uses your 2nd example. Mages with parma magica of 3 or less, can protect a group of people with a resistance of 0.
A mage would add his own form resistance, not that of the mage protecting him. (I think, it's an interesting question)
A mage may desire another mages protection if his parma magica is much better, 4 or more better.
Or, if he's a non-hermetic mage, and doesn't know the parma magica.
Or if he's still an apprentice, and hasn't been taught it yet.

It says that the effective score is reduced by three; BUT if that reduces it to 0 or below, it still counts as "MR 0".

The possible IC reasons a mage might want the protection of another mage are varied and obscure. I believe the word "this" refers to the entire process, not specifically limited to the situation if the initial Parma score is 3 or less. The point is that any mage so protected uses their own Arts as bonus, not the protecting magi's.

That line is there to answer predictable questions. :wink:

(Three reasons that jump immediately to mind are... the protecting mage has a MUCH bigger Parma; the protected mage is unable to perform the ceremony (unconscious, or as TB suggested above, or...?); or some obscure IC social restriction - perhaps a lost Certamen bet.)

Or because he's got a Flawed Parma of some sort.

Even a flawed Parma 1 is better than Parma 0 from a 1-3 source.

And even a magic resistance of zero is better than none... :wink:

[size=75](As penetration is sometimes less than zero).[/size]

Magic resistance of 0 is HUGELY better than none at all.