The new iOS 10 Home app uses the HomeKit framework to do some things most of the 3rd party apps didn't do before (maybe it wasn't possible)...namely, using a Lutron light switch (or Pico) to set a scene (Caseta) or turn on other lights. And, similarly, a recent update to the 3rd party Home app by Matthais Brutella takes advantage of "non-readable characteristic as trigger event". Anyways, it looks technically possible to use the state-change of one Lutron light to set a scene (or just turn on other lights). This solves similar problems as using the Pico switch to set scenes.
I got very excited the other night after setting up one trigger and scene. It actually worked. Turning on the floodlights then, through the HomeKit Automation, turned on the desk light. Another HomeKit Automation allowed the Floodlight switch to turn off both the floodlights and the desk light. However, it was flaky. Sometimes it worked and sometimes not. I turned on/off the conditional setting for "only trigger after sunset" and it worked again but later it wouldn't work. Now I can't get it to work no matter what I try. The 3rd party app Eve says the Rule (automation/trigger) never runs which may be a clue.
When the trigger did work (whether the floods were on/off) it was directly turning the desk light on/off as iOS 10 allows for that. The third party apps only allow the automation to turn a scene on/off. So I created a HomeKit scene with only the desk light in it and tried triggering that but that didn't work either. Now nothing works.
My Home Hub is an Apple TV 4 running tvOS 10 and I'm using an iPhone 6 running iOS 10.0.2. Has anyone else got this to work reliably? I haven't tried restarting the Apple TV but could. The state of a Lutron light isn't exactly a "non-readable characteristic" so it should work. Maybe an iOS update is needed?