I just installed Stephenson's rocket in Virtualbox and GRUB_CMDLINE_LINUX_DEFAULT was not set to quiet splash vga=0x0318, like I expected. I was not using UEFI, /sys/firmware/efi does not exist on the system. It has a very small hard drive, though, which makes the system only get a root partition with the automatic installer of SteamOS.
Looking at the post install script, the ISEFI variable at all should not be set in this case.
I just installed Stephenson's rocket in Virtualbox and GRUB_CMDLINE_LINUX_DEFAULT was not set to quiet splash vga=0x0318, like I expected. I was not using UEFI, /sys/firmware/efi does not exist on the system. It has a very small hard drive, though, which makes the system only get a root partition with the automatic installer of SteamOS.
Looking at the post install script, the ISEFI variable at all should not be set in this case.