twaddleI don't think UAC is an excellent security layer at all and I always disable it as a matter of course as I hate being asked if I'm sure I want to do this that or the other. I notice that a lot of the audio tweak sites are still suggesting turning off UAC too.
It's a pretty decent one. It isn't useful like in and of itself, but as part of defense in depth, which is the only real kind of security. What it prevents is something like malware breaking in via an insecure user mode app like Java or your browser or something and then embedding itself in the system. It would have to request escalation, which hopefully you'd deny. If it can't get that, then it can only infect your user profile, which makes it much easier to remove (you can remove the profile, if nothing else).
It is just one of a bunch of layers of defense like a virus scanner, firewall, ASLR, driver signing, and so on that help keep you safe. Yes it does require you to make decisions, but then security does require a user to be proactive.
In terms of audio tweak sites, the problem is that most of them don't really understand or test their tweaks. That is true of a lot of the tweak stuff for anything out there. Things become "magic spells" that people don't understand, but some guy did one time and it worked so people keep doing them, without understanding why.