Board Thread:General Mod Discussion/@comment-26841670-20180310184629/@comment-33185350-20180311222858

I wouldn’t let players get to the highest level of knowledge in multiple skill trees. They should have to focus on one. However they should still be able to learn lower-level skills from other trees. For example, Dwarves have taught Elves (like Eöl, as you said) some of their crafts, but they have secrets (like their language) that they keep to themselves.