Cases in Chapter 4 Hocus Pocus (by Jackson) address that improper timing topic: Manipulate their own GAAP interpretation on revenue recognition rules (lease contract on Xerox, changes of accounting policy on allowance method on Insignia). Please think about and discuss: (a) why do their external auditors, or internal auditors, or audit committee, or controller approve these interpretations? (b) Any other observations from these cases? Yet your discussions are not limited to these points only