Does using a smart vapor retarder in a hot humid climate make sense? It seems to me that its low risk. During summer and high humidity situations it can open up past class 3 vapor retardancy to allow inward drying, and during winter, it can prevent interstitial condensation in an insulated cavity. Any thoughts on this? 

Context: CZ1, fiberglass only insulated cavity, vapor open (38 perms) exterior weather barrier, rain screen.