The first two paragraps can easily be misunderstood as the ABI being optional. When it's not. I'm talking about the paragraph: "Differing D implementations, however, are free to innovate upon the memory model, function call/return conventions, argument passing conventions, etc." It should be made more clear that this is only for non-x86 targets.
Change this to: "Implementations of D on different architectures, however, are free to innovate upon the memory model, function call/return conventions, argument passing conventions, etc."
Fixed dmd 1.057 and 2.041