Each Workflow step can have Conditions, Validators, or Post-Functions associated with them. Having these features associated with the Clone and Edit operations would allow easier manipulation and greater control of issues:

• Associate a permission with the Clone permission to restrict who can clone on a per-project (or global) basis
• Add a Clone post-function to delete certain fields that would be undesirable
• Check the value of a certain field is populated after an edit (or process the field contents)

In my particular use case, I wish to see a series of custom fields be cleared out when an Issue is cloned from another.