Do we know what happens when you put scholars into a library without books, bookcases, chairs, tables and blank scrolls and/or quires to write on? My doctors aren't really doing anything, and short of deliberately injuring my dwarfs putting them in a library seems to be the only way to train their skills.
I think they can ponder without a table, and get into discussions as well. However, the "skill gains" from leaving your doctors as scholars is still pathetic. Its better thought of as "rust prevention" than "skill gain."
My advice if you are looking to get a library going is to embark with the academic skills you want otherwise it will take decades of in game years to get anything other than dabbling. I personally always embark with a doctor. Now ill just slap some writer points on there as well and call it good.
Theoretically (bear with me I rarely adventure. It's Dwarf Fortress through-and-through) could you make an adventurer with high doctor skills, some writing or teaching/student and 'settle' the bugger in a pre-made fortress?
Yes. People have already talked about making a "scholar" to visit their fort and "argue" values of their dwarves until they get them all as "values hard work, hates leisure time!" People have also been retiring adventurers in their forts to gain super-soldier champions as well. No reason you couldn't do this with adventure mode. Make a ton of demi-god adventurers with scholar stats and skills. You could even run around trying to level these up with discussions and such before dropping him off and retiring at a fort. IIRC, you have to start your adventurer off from the fort in the first place to gain full-citizenship. You could possibly achieve it through becoming a hearthperson, but the issue is that you need to become a native member of that fortress's group. You know, the bug where petitioned citizens can't become scholars?