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.
Use Mobipocket software to convert PDFs to that format so you can read them on Kindle.
Non DRM Mobipocket format is already supported on the Kindle - just drag and drop.
DRM is not to prevent other files from being readable on the Kindle.
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