There is consensus among team and community developers to stop supporting the installtointernal script. Installation on eMMC/NAND provides a marginal performance gain on most boxes, but adds significant complexity to the installation process and the number of installs that go wrong and need significant hand-holding to correct is proportionally high (much too high).
Creating releases is fun. Finding bugs and resolving them can be rewarding. Supporting users with the same installtointernal issues over and over and over makes you hate life, Android boxes, and users. The script is gone. The script is not going to return (the risk is our sanity, not your box).