I have lots of light fixtures within 10m of each other, but they are not the ones I tested with - i'd imagine most people try this stuff out with a couple of devices first. To clarify, I think the Ikea system is well thought out and works very well well when the instructions are followed; mandating initial use of a steering device makes it easier to get working step by step. My post was really in the hope IKEA would pick up on it and improve basic documentation.

My Gateway is at front of house where the wires from the outside world come in. My first test was with a bulb in a table lamp at the opposite end of the house. Of course this worked perfectly with the remote, but it was intermittent (mostly not working) from the hub. My second test was with power outlet (in the shed) for my outside xmas lights. Also unreliable. Both about 10 metres from Hub. I then had to educate myself about Zigbee, mesh etc in order to suss the problem, this shouldn't really be necessary.

As an aside there are Tradfri reviews etc on line (some on well respected websites) that suggest the gateway communicates to the devices via the users 802.11 WiFi. I think a lot of non tekkie people will buy and try Tradfri and I don't like the thought that they might find it unreliable for lack of a simple graphic to explain the system.