The most annoying thing about esoteric wiki articles is missing context. Most of them explain the thing but not HOW or WHY it matters or why it is important.
Itanium seems to have, in any case, shown us that exposing the microarchitecture for the sake of performance is an antipattern.
This post intrigues me and piques my curiosity -- it's an interesting fork of the Intel x86 family tree that obviously didn't go anywhere. But the context for the submission is also interesting: does it relate to some emulator work that the submitter is doing, for example? Or is there a potential vulnerability that could be exposed by the existence of these instructions? Or was it purely the discovery of this learning that caused them to want to share it? HN doesn't provide an automatic means to share that context with a link submission, which is a pity. But I for one would love to hear more from the poster.
And to that, I also wonder why many posts were posted when they don't come with any comment.