That might explain why I haven't noticed any errors. I have hardly ever clicked a link inside Book Details. Nevertheless this is what happens when I do it now:
- Open book list - no grouping
- Open book details for Joe Abercrombie - The Blade Itself
- Tap hyperlink for Joe Abercrombie
- 3 books by J.A. displayed in booklist. Group drawer has Authors - A - Joe Abercrombie selected
- Open book details for Joe Abercrombie - Before They Are Hanged
- Hit back button - shows me 3 J.A. books in booklist
- Hit back button again. Shows me all books in book list. Group drawer displays expanded Authors (by first letter), no item selected
- Hit back button again. Book list still shows all books. Group drawer back to No Grouping.
I don't think there was any unexpected behaviour here.