"Sure, that works if you are talking about one machine. Now imagine that you have 100 identical servers, each with 4 network ports. Think of the administrative overhead (every single one of those 100 machines will require a different 70-persistent-net-rules.net) and the chance of making silly mistakes.
With Fedora's approach, you will only need to write one config per hardware platform, which is vastly more manageable for large organizations."
Youve heard of scripts right? Tools like puppet or cfengine? Why are you managing 100 hand and custom built servers?