Sleipnir, when you download it, is deodexed. Normally, however, when you flash it, it odexes itself so that once it has been installed, it is odexed. Deodexing makes theming easier before you actually flash the ROM onto the device, and odexing makes accessing of the system apps quicker because they're already partially decompressed. This way, you get the best of both worlds. I'm guessing that Stark was theming post-flash, so I went ahead and made a deodexed (post-flash) version for him
In other words, De-odexed means all system apps are .apks, fully compressed. Odexing creates a .odex file associated with each system app .apk, making them partially decompressed. This allows the device to access the app's data more quickly, because it doesn't have to decompress the full app before reading it (part of the work is already done).