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Fixes: None

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Code review: None

utils/python/CIME/SystemTests/system_tests_compare_two_clone.py

@@ -18,6 +18,9 @@
 
 (3) _case_two_setup
     This method will be called to set up case 2, the "test" case
+
+NOTE: Currently assumes that only one build is needed - i.e., there are no
+build-time settings that need to be changed between the two cases.
 """
 
 from CIME.XML.standard_module_setup import *