That is a nice solution now that I think of it - once fastai becomes available as a conda / pip install this will not require any code changes, this is much nicer than the solution I found 
I was thinking that maybe there would be somewhere I could symlink from to have the library available globally for any new directories I create - sort of like emulating it being installed while still giving me an ability to automatically reload it.
BTW how to do the symlinking if anyone should wonder:
-
cdto directory with workbook ln -s /path/to/fastai_repo/fastai