Regenerate master configs?

[aseques]

There are some moments I'd have need this, basically:
.- I screw something of the configuration and I want to recover it to the default
.- I want to change any of the templates (i.e. DNS) for all my company, for example if I replace ns2.example.com to dns.example.net (if outsourcing DNS).
.- I want to adapt the templates and test them because when upgrading from rc6 to final nothing destroys my personal configurations

Those are the cases I found so far, the 3rd one being the most dangerous because then I have t rely on my copies totally.