Of course, you don't have to care about the layers underneath as long as they are bug-free and do what you want.
I'm sure that in future articles Matthew will assure us that EFI implementations are bug-free flawless jewels of perfect software engineering which work brilliantly on all operating systems, just as we would expect from the geniuses and wizards who work on BIOSes. (It's true: they do, as long as the set of operating systems consists of one single version of Windows on one single hardware configuration and it was only booted once during testing while holding a horseshoe and a rabbit's foot above the monitor.)