My immediate thoughts - these may hange upon reflection
That kinda depends:
If you learn about a tradition (we'll take gruagachan as an example) by studying the results of their magics, you'll learn about what you see.
ie
- You get a few people that have been granted blessings via GiBl effects and keep the in your lab for a season or seven, while you try to figure out what's going on there. You'd learn about Blessing only.
- You get hold of people affected by a variety of effects and study them in the lab. This should take more time, but provide wider insight, probably into the whole tradition (well, the magical aspects anyway).
- A friendly (and perhaps foolish) gruagach teaches you about the principles of his magic for a season. You might have to mull that over for a bit longer and you might have to invent the first PeVi spell using experimentation, but that's about it.