I recently stumbled across an interesting series of articles submitted to last year's 'Meaningful Play' conference and one of them was about Ars Magica! 
Great tip! Thanks!
For me personal (pen and paper) rollplaying in general was the reason to learn english because the translated books where sometimes bad translated, if there was a translation at all.
So I started from knowing next to nothing in english from be forced to learn it for 1 year trough normal formal education in school to be able read trough most books without needing to look up what something means.
I saw similiar things to happen with people watching animes (jap. comics) who then tryed to learn japanese so general its about generating a high enough interest in a person to learn about something.
For Ars Magica its then not just the medival part I try to get facts about but also still to fill some of the gaps I have in my english.
Pretty much the same here-
That was a very interesting read. Thanks for pointing it out!