The problem with Sense Holiness/Unholiness is also that it would need to be of Divine source otherwise its of no use at all because the deception of the infernal trump over everything else.
All item creation with divine source I know so far are Wondrous Items as well es craft amulets and Kabbalah both Jewish tradition.
Even to do something with a similar effect is not possible because of the 0 penetration limit for craft amulets and wondrous items.
(Unless the crafter have something like the sense of mystic virtue from HMRE 53 also)
Kabbalah only create Golems so its of no use.
Because a spell with divine source would break hermetic limits and so become a ritual for Holy Magic according to our interpretation its also not possible for a Holy Mage to create items that can see trough Infernal deception without a breakthrough (Sources for a Rituals in items breakthrough would be Mercer Portals and items of Hyperborean source).
Also sorry that I didn't and still don't understand what a item of virtue (or quality) is. ^^
..... Hmmm that gives me a idea that my magus could try for a breakthrough that allow Holy Magic that see trough infernal deception as normal spell and not as ritual once he start to focus on intellego during our game. (After all he is his own research source for this)
Actually there are cases where hermetic magic can detect the infernal- essentially when there isn't a demon to back up the deception. Infernal vis, for example, can be determined to be as such. Infernal auras with no resident demons is another such case...
Can a breakthrough change a spell from a required ritual to a formulaic spell? For example, could I make a breakthrough that made it so that you could cast a Year Duration spell without it being a ritual and costing vis? Could I make a breakthrough so that you could create permanent effects without vis cost and without it being a ritual? Because that's the equivalent of what you're proposing.
I'd say that he could certainly be a research source. But remember that each source is usable only once. You'd have to find other research sources once you'd examined yourself.
True. But it lists the breakthrough as costing 70 (!) breakthrough points (i.e., even harder than a hermetic breakthrough). Vis-less enchantment costs 65 and comes with some difficult decisions (i.e., accepting Warping points instead of spending vis).
So I think it's fair to say that while it would be possible to make a breakthrough to allow non-hermetic holy effects to be cast as a formulaic spell, it would be an uphill climb (likely at least 60 breakthrough points, if not more).