Default combining rule

As stated earlier, the default combining rule is appropriate for only two scenarios:
  • You want the description as a whole to be true only if all the individual descriptors are true (this is the most common scenario).
  • You want the description as a whole to be true if at least one of the individual descriptors is true.

If you want the description as a whole to be true only if all the descriptors are true, then set the Optional attribute of all the descriptors in the description to false (the default setting).

In contrast, if you want the description as a whole to be true if at least one of the descriptors is true, then set the Optional attribute of all of the descriptors in the description to true.

You should not use the default combining rule in any other scenario where you have multiple descriptors in one macro screen, unless you understand the rule and its implications thoroughly. For more information see Default rule for combining multiple descriptors in one macro screen.

Also, you should not set the Optional attributes of multiple descriptors in one macro screen differently (some true, some false) unless you understand the rule and its implications thoroughly.