Icarus, the QRH guides on and provides checklists for emergencies. However it is nowhere near 99% of the decision to be made!
An engine fails .. Complete QRH.... What next??? The QRH does not tell you where to land. It does not tell you how much fuel you have. It does not tell you how heavy the aeroplane is, what weather and icing there is, terrain, destination runway length, instrument approaches, engineering support, passenger handling, dealing with cabin crew, notifying ATC. The list goes on. And this is where the experience kicks in! Prioritising and managing..
Procedures are there to be followed, pilots are there to manage the procedures and safety. If you need a book to 99% fly an aeroplane you're in the wrong job. Otherwise we would have been engineered out by now. Every flight is different, and not every issue that could arise in flight has happened yet. What happens when there is no checklist? And multiple failures. Where do we start??
Geez wouldn't our jobs be easier if we didn't have to make decisions, some of which under pressure and time constraints.