I have a Homey Pro 2023 with 146 devices connected to it (probably around 90 % plus is Z-Wave, the rest is Zigbee and Wi-Fi).
I recently made a flow for night mode, which (amongst other things) turns off all the lights in the house except exterior lights. That makes for around 26 lights, all controlled by Fibaro Dimmer 2 or Fibaro Double Switch 2.
If I make the flow in such a way that it just tries to turn off all of these in parallel, it won’t work. I end up with several lights that time out and refuse to turn off. Because of this I have grouped the lights by floor and put delays between the groups. This has worked perfectly so far.
What puzzles me, however, is that another part of the flow is used to set the “forced brightness” parameter for all Fibaro Dimmer 2 (24 of them). When I do this, I can just send all the commands in parallel, and they execute immediately and flawlessly.
Why this great difference between turning the lights off and setting a parameter? Shouldn’t turning off all the lights be just as easy? 
