I'm having really strange fluctuations with my quant. Comparing to my past performances:

Official Guide: Questions 200 - 224 - 1st time 23/25, 2nd time 16/25
And again: Questions 175 - 199 - 1st time 20/25, 2nd time 23/25
And again: Questions 150 - 174 - 1st time 21/25, 2nd time 24/25

Was the 200-224 fluctuation just bad luck? That's a large difference. Was it just a bad day? Maybe I was tired and wasn't thinking straight? But other than that, the other fluctuations show some improvement. So that's pretty good, but I'm concerned about a bad day, will my score fluctuate -28%?

Just as practicing for the GMAT is about consistency, taking the GMAT should be about consistency. Test scores should be the average of 3 sittings, over 3 days (or 1 week). Maybe shorter tests. The current system allows too much of a chance/random factor. On a good day, you'll fluctutate up, on a bad day, you're doomed.

Yes, it will require more resource commitments from candidates but given that they have already committed so much to preparations and will commitment a lot more for the applications, shouldn't the GMAT score be as accurate and representative as possible? Minimize the fluctutations, if you're a 700, you'll score a 700 on average. Wouldn't you want your GMAT score to be as accurate as possible?