This is just a drive-by comment: making a new binary package just for a configuration file snippet doesn't seem like a great tool for the job. Usually a debconf option (perhaps set at low, not-shown-by-default priority) is the tool of choice for scenarios such as this. This would make it easy for sysadmins to have this set by default via installer preseeding or your preferred choice of Debconf backend, and also make the option discoverable using standard system tools. For gurus running Debconf on low-priority mode or using the expert installer, this will also allow including a blurb about why this *isn't* the default and allow making an informed decision.
Downstream customization issues such as this are just what Debconf was made for. Using that would be preferable to making a new binary package with just a single text file, say.
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