Final answer:
Choosing guest checks that are difficult to duplicate and shredding guest checks as soon as cash banks are reconciled are not considered best practices under a manual guest check control system.
Step-by-step explanation:
Under a manual guest check control system, choosing guest checks that are difficult to duplicate is not considered a best practice. It is important to use guest checks that have advanced security features, such as watermarks or unique serial numbers, to prevent fraud and counterfeiting. Shredding guest checks after cash banks are reconciled is also not a best practice, as it is important to keep a record of all guest checks for audit purposes.
In contrast, accounting for all guest checks at the end of a shift and maintaining a record of the guest checks issued to each server are both good practices. This helps ensure that all guest checks are accounted for and reduces the risk of errors or theft.