The evaluation reports specify appropriate gradation. The gradation should not be changed unless an engineering evaluation acceptable to the building officials specifies that changing the gradation and concentration of the sand will not degrade the stucco. The stucco manufacturer is not given the latitude to approve variations in the gradation of the sand.
In residential construction, there are those who believe that $0.79-per-tube caulk applied by an untrained person constitutes waterproofing. It does not. A sealant joint is an area where considerable movement is anticipated. If a sealant joint is made without a bond break on the back of the joint (backer rod), the sealant joint will start to self-destruct when movement occurs. Always use backer rod when using a sealant in any exterior application.