Rights of users to jobs come in three forms:
Users can always view job definitions, slots or assignments, but these restrict their ability to change or delete them.
Inheritance works slightly different here than it does in tools: for a given job if the user's rights to "Assignments" is "(undefined)", VSys looks to the job's "Slots" rights. If that is "(undefined)" it falls back to the job's "Setup" rights. If that, too, is "(undefined)" then it looks to the job's job group, then back to the user's roles and the default user rights as needed.
Job associations, if enabled, are not subject to the "Assignments" rights here. A user's rights to the job associations of a person are defined by the user's rights to edit that person, not by the job association's job.