So one of the first things you think of when someone is comparing gaming performance is draw calls? I'd think FPS and latency would easily come first. Maybe smoothness, or consistent frame times as well.
Do you seriously think draw calls, or is it that because they are talking about a new lower level API, it comes to mind?
I already explained why I believe they said that. I've also answered your question about the legitimacy of the claim.
What we are talking about is a lower level API. So, of course that's why the 10X draw calls comes to mind,
first thing. I also think it will improve all of the other metrics you mentioned just like Mantle did. Do I think that the average FPS will be 10X as fast? No, of course not. Nobody with 1/2 a brain and any knowledge/experience of these API's would expect that.
10X the draw calls I expect. That's why I believe that was what they were talking about. You liking it or not isn't my fault or something I have to agree with you on. That's why I said, YMMV.