Whilst HTBJ may not be quite as old as the bible, it does cover the fundamentals very well. The big issues such as jet response compared to TPs, momentum, Manoeuvre envelope, coffin corner, icing, LDR/LDA, etc,etc. Perhaps if new pilots read and understood books like HTBJ rather than cramming for ATPL multiple guess exams, we wouldn't see so many Loss of Control / Stalling accidents.
Most of the Qatar q's were about aircraft performance. All the best!