Hmm. Yeah, it could be latency or hiccups making it seem random, then, since I play RDM as a secondary and have not had a time when I didn't know when Dualcast would be active. I run at about 80 ping though my connection is stable, so it would make sense if this is the cause of the issue.

The way the game handles the status frame is a bit problematic and leads to a lot of weird interactions across ticks, like Hollow Ground activating, taking the CD, yet you still got hit with someone it should shield you from,and you die. It's unfortunate but I am not sure if anything can be done with regards to RDM besides improving the underlying code and infrastructure of FFXIV itself.