I verified that the above concept…using a “dummy” X10 device to create a window for a random event to occur will work. I turned the dummy device on and off manually for testing, but it should also work with the device turned on and off through actions.
One comment – I had trouble making the random setting work for shorter time intervals. After trying several between 30 seconds and 5 minutes, I set it to 15 (as in Lee’s example). Only the last one worked.