I can see a
use for table specific 'Custom columns' (Authors in this case).
The Issue is 'user support'
How many of Calibre Users know that Calibre is not a 'Flat File'?
Now try and explain why you attach the Column to 'authors' and not 'books_authors_lnk'
Forgetting those user issues
How do you support a decent UI and data integrity for these
other tables
