DRM is not to prevent other files from being readable on the Kindle.
DRM refers to the fact that you can't view Amazon Kindle books on other devices (including your computer), or on other Kindles - i.e. no sharing, the purpose of DRM.
Non DRM Mobipocket format is already supported on the Kindle - just drag and drop.
The hack allow ENCRYPTED Mobi files to be read on the Kindle. So you can buy a DRM-protected mobi book and read it on Kindle.
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