As for why it's meaningless: Well, it's just the sort of dismissive platitude you hear from people when they don't want to continue thinking about something but want to seem profound (or even funny, as the phrase "is it what it is" seems to have become a kind of in-joke with many people I know). And yeah, I know the whole grander idea behind it, A=A, etc. from old associates who kept trying to sell me on Rand years ago. It still strikes me as an unnecessary, lowest-common-denominator kind of gimmick.
But let me read up before I go any further. Thanks for your response.