On the one hand, several blended-learning programs are continuing to use curriculum from one online provider, and although it doesn’t give them the customization they may prefer ideally, its simplicity and reliability are worth the tradeoff. Carpe Diem schools and the Flex Academies exemplify this–and neither seems to be complaining nearly as much about the technology.
Horn's post as a whole is a handwavy cop-out, but I'd say the above paragraph illustrates just how fucked K-12 ed-tech is. Which products, exactly, is Horn referring to? You will never know in ed-tech, because that might upset somebody actually important. God forbid educators might have a drop of honest opinion even accidentally fall on their lap regarding a Holy Vendor.