So what? If AMD wouldn't give details about their bugs how would Intel know which is which? Easiest to not optimize any non Intel CPUs which they can now do under the settlement if they just put a in tiny disclosure. I hope they explain why.
re: bugs: Nothing but Elmer/Intel FUD.
If it's so awesome for Intel, why didn't they already disclose their VendorID-based compiler/library behavior, with explanations? Why hide it? Why fight to keep hiding it?
(Answer: because the excuses are BS and would/do not survive scrutiny.)
Like so many of these issues, I bet anything that this one does not turn out the way you think it will.