[NOOB] Nodes communication when gateway is down

[dakipro]

Hi everybody.
I am still in process of planning and then building home automation system, I am thinking about using MajorDoMo controller (just because I can php). My biggest challenge is my wife (still speaking about home automation now ) as she is very against it, since I tried it many times with commercial products that never worked "exactly" as we would like it. It was always a compromise of some sort, some delays or some malfunctions causing us not being able to turn on the light for example.
I've been reading about MySensors and arduino and think that I could have much more control and achieve exactly what we would like to have.
And that is very simple, reliable system that we could always override and "have control" over, without waiting for pc to boot or something.

Sorry about the long intro, but I didn't find exact answer to my question:
Light switch scenario: node1 that will turn on/off one light via relay. Node2 that is a "click" switch sending signal to node1 to turn on/off the light. Then the node1 (relay) will send message to the controller about its latest state.
Node 1 (relay) will also be able to receive signal from controller/node3(same switch as node2)/node4/... Direct communication would have almost no delay and controller would still know the state of the light, and also being able to control it. When I "prove" that it all works fine, then I would build on the system.
Would this work? Would this work if the controller/raspberry pi/gateway is down for whatever reason? Any better approach/link to this very simple and basic case?

Thank you very much for an awesome platform, I can't wait to order bunch of sensors from the website and start playing around!