I still do not understand the rational of why reducing the power output
> of the router, disabling SSID, or enabling MAC filtering will secure a
> WiFi network.
>
Who said it would. I will use every pratical tool available to make the
network as secure as possible.
I will attempt to explain the reason to you for reducing the range of
Wi-Fi router:
If the area I need to cover is only say 50 meters, why have a system
that can reach a couple of hundred meters? It won't stop a determined
hacker but 'passers by' will have less chance of detecting the network
which can only help make it more secure.
Take it to extremes. Person 'A' Has a wireless network that has a range
of 10Km and person 'B' has a network that has a range of 10m. Who will
be at greater risk from a hacker?