The NA Client Services team has noticed that once a rule is added to a field in Maestro, no further rules of that type can be added to the field. This presents problems in some situations - for example, Dustin pointed out the use case of needing something to be visible only on a receipt OR on a specific job step. Since the receipt visibility rule is separate from the standard conditional visibility rule, it's currently impossible to accomplish this because you can only add one of the two rules.
Is there a way to add multiple rules of the same type, or combine categories of rules in the same script?
... and there are some cases where form authors might want to define multiple validation rules which execute in parallel. It would reduce the amount of code required if these could be defined separately, rather than having one huge script with logic to handle two cases (the difference can be 2 conditional statements vs a full script).
All visibility rules are essentially conditional rules. The "Show on Receipt" rule is just a shortcut to adding a "Show if..." rule with the value "Util.isReceipt" - so to achieve what you're after, you can just add a conditional visibility rule with the appropriate combined logic (i.e. Util.isReceipt || <job step>)
As David Foster has said, there is no need to have two rules of the same type as you can use conditional logic in your current rule to achieve the result you need.