Why do some people hear from Apple support "I never heard of this before?"
Here are my thoughts on this:
If all people of the support would tell all customers the same ("yes we know, yes, we're working on it") what could be bad about that?
Quite simple: they admit it. They admit: yes, hundreds of people are calling in every day. Yes, it's a big issue. Yes, everybody has this problem.
Then some people - including the press - could start to ask questions. Questions like "how could this have happened? Why did quality control not catch this?"
If the problem is due to software (and it seems very much like it is) and if all 13"rMBP are affected (and it seems very much like they are) then it is obvious, Apple has done a terrible job on quality control on the combination of Mavericks build 13A2093 and 13" rMBP. (and it seems very much like they did)
But what if every second ot third customer of a 13" rMBP gets to hear "oh, really? I never heard of this before".
Suddenly, it sounds very different. Suddenly, it sounds like "there are only a few 13 inch rMBP affected".
Which leads to "how could have Apple possibly catched this during testing or quality control? All devices which were tested by Apple did run okay."
Guys, to be honest: I can not believe, the internal communication at Apple could possibly that bad that some supporters really never heard of this before. They have to know by now. All of them. I am sure, support is split up in teams. I bet you, these teams have at least weekly meeting to discuss the latest procedures and news.
Sorry, but I strongly believe: if a supporter tells you "this is the first time i hear about this" - that person is not speaking the truth.
Same applies to me for managers of Apple stores, etc.
It is politics (no, we do not have a big problem, just a small issue) and marketing (no, you do not need to wait, buy your 13" rMBP now).
That's what I believe.