OK, so House of Hermes: True Lineages states “These sorts of virtues are often Hermetic Virtues that can be taught to the Gifted” and then gives an example of someone inventing Life Boost. What exactly is the mechanic? Anyone who has learned the virtue from the original teacher can take a season and teach it to someone else? With no penalty from already having Arts opened, just like Parma Magica is not penalized because it is designed to work with Hermetic Magic?
Is Affinity for Creo a legitimate Hermetic Virtue, or is there some unstated reason that Virtue is off limits?
If someone developed Original Research into developing Affinity for Creo, and did not have that Virtue, would he automatically learn it once completing that research?
When teaching others, do they also gain the ability to teach others? So, if Zaccheaus teaches Apolloyon Affinity for Creo, can Apolloyon teach Gaston Affinity for Creo?
The logic I use is that if it is a virtue, that suggests it isn't integrated fully into Hermetic Theory. If you don't have the virtue, you need to earn it via an initiation or have someone take it the extra step and do the full hermetic theory integration.
If it were fully integrated, it'd be available to anyone who has a score in magic theory - and learning it just involves a season of study. Be really careful about this, though, since this means such knowledge would quickly become commonplace throughout the Order.
Making a supernatural virtue into a hermetic virtue, or making a hermetic virtue part of general magic theory are both covered by the breakthrough/original research rules. You'll find these in both HoH:TL and Ancient Magic. Learning a new hermetic virtue from someone who knows it is usually done via initiation - for which you'll find rules in any of Mysteries: Revised, Ancient Magic or HOH:MC.
Affinity seem an odd virtue to pick for integration, though, since to me an affinity in itself suggests an entirely mundane natural talent with that particular thing. Just being really good at it through natural talent. Of course, even that -could- be a mystical gift of awesome bestowed by some otherworldly creature... this is Mythic Europe we're talking about after all!
Assume that this has been done a couple of times since magic entered the world - which is why we now have arts as accelerated abilities instead of normal. What it means is that you do a lot of work into the basic understanding of the art, and correct some basic understanding issues people have had.
Offcourse, getting affintiy for an art after a century of working with it, isn't that great a thing. And the teaching of it wouldn't really matter that much since few sagas run long enough for several centuries. Offcourse, it should still be possible to a talent for the art, so you get an additional affinity for the art... The exact rules for that is something to come up with once you get to that point.