Separate tables for worklists as opposed to workbaskets are more efficient.
For example the Assign-WorkBasket GetNextWork ListView does not need to ignore pxObjClass=Assign-Worklist rows.
At the same time the Assign-Worklist pyMyWorkList Report Defintion does not have to ignore pxObjClass=Assign-WorkBasket rows.
Both Assign-Worklist and Assign-Workbasket extend Assign-.
The exposed columns for these classes are the same because their corresponding Properties are defined at the Assign- level.
The major difference between Assign-WorkBasket and Assign-Worklist is Security - for example the canPerform Access When rule is defined differently, WBs can be assigned a list of Access Roles, and be associated to a WorkGroup, etc.