I've been chatting to Dan Ramsden to see what else I can dig up for you.
He wondered whether you know about the IA Institute (http://www.iainstitute.org/) – probably the best source for resources and recommendations.
They maintain this: https://docs.google.com/spreadsheets/d/14y4PWND-xdn6a64b8EYCeuwi2SJRrEwUvgEktDwKP2o/edit#gid=0
They also have a resource library of articles and books etc
He also said that there tends to be a shift to quite an academic approach the more experienced people get. There’s a whole ‘re-frame IA’ movement that's pretty academic (http://reframe-ia.org/).
He doesn't hear masses about being an advanced practitioner, perhaps because IAs love the phrase ‘it depends’ so much – so they’ve never developed a concrete body of recommendations for advanced challenges.
He's also happy to have a chat with you to discuss it further. If you want to do that, let me know and I'll send you through his contact details.