Well even with LMCE handling everything, the light switches etc, are still autonomous...
but think about it.. when the power goes out... so does everything else, right?
At worst, when LMCE goes out, your land phone line goes out... but we all have cell phones, right?
Not to say that redundancy is a bad thing.. It's what we are striving towards.. but in the mean time, it's not a bad thing to trust your house to LMCE.