Kris, I think I understand Stringify's flows, but less certain about the true meaning of "device" as used in cswheelock's post.
I like the idea of having a drop-down box for an action to decide whether a flow can be run by Alexa's "turn on" or "turn off" phrase. That's basically the same as what Yonomi seems to be doing, except instead of a drop-down box setting, it infers that routines with "off" at the end of their names should be triggered with Alexa's "turn off" phrase.
I also had another idea, but I think I like your's better. Still I'll throw it out in case you or somebody else can make something better from it.
Stringify's flows are made up of triggers and actions. For some actions, like turning on a smart bulb or light switch, the "opposite action" is clear. For other actions, like setting the thermostat, it is not clear. So, for those actions that clearly have an opposite action, Stringify can infer what to do. Lights and switches would be turned off, thermostats would be...hmmm...either executed again or skipped, I'm not sure.
You might even be able to select, for each action, whether it is part of the flow's "turn off". Right now, every flow is in response to a "turn on" trigger. Maybe Stringify can make intelligent decisions--propose to the user--what the flow would be for a "turn off" trigger. Of course the user must be able to override what Stringify suggests.
Your idea is more powerful by allowing the user to make up a "turn off" flow that may do different or additional actions. But for the gentle user, it might be nice to help them out by suggesting a "turn off" flow.
One last idea. Allow flows to have multiple "trigger-flows" (not a great name) that respond to different phrases that are supported by Alexa. When initially created, a flow has only one trigger-flow that is triggered by "turn on". That's what happens today. However, the user can add additional trigger-flows, and Stringify can even help out by creating an "off" flow from an "on" flow for actions that clearly have an opposite action. After that, Stringify would allow users to modify the flow in any way they like.
What I like about this idea is that it can make flow ideas in the Discovery more powerful. Being able to package multiple trigger-flows into one flow idea would make them more powerful. I'm sure some flow ideas would benefit by being to react to different trigger phrases. (Of course, other would not, and probably complex flows would not.)
Anyways, just some dumb ideas to kick around. Thanks a bunch for getting back to me and running an idea through me. Much appreciated.
(I probably should have posted this reply in the "Things suggestion and ideas" category. This thread is starting to morph into ideas.)