It is possible with disabled secure boot. Windows 8 doesn't need Secure Boot or even UEFI to work. It's only about the "Certified" sticker.
And theoretically, Grub (or something) can have the key signed.
And theoretically, Grub (or something) can have the key signed.
More importantly, how much would this sway a decision of a consumer (one place where I find 'consumer' better than 'customer') who sees two similar laptops with very similar prices except one say "With Windows 8" and the other says "Windows 8 Certified".
Could the manufacturers not come up with their own marketing campaign or something like "OpenSource Initiative Certified" or something like that[obviously they can't use OSI's name but you get the idea].
And you dont think that is a political choice?