Hi Rich,
I think that you probably know enough about the content, Tactics and patterns behind the GMAT that you have the capacity to score higher than this current range of scores. Thus, there's a reasonable chance that there are issues with your 'mechanics' (how you're taking notes and working through individual questions). "Review" is an exceptionally important part of the GMAT training process; your ability to define WHY you're getting questions wrong is essential to defining the areas that you need to work on (and the specific things that you need to 'fix').
As such, I'd like to know a bit more about the last CAT that you took under realistic conditions (timed, taken in one sitting, with the Essay and IR sections, etc.). If you have filled out a full Mistake Tracker Excel, then you should email it to me and I'll be happy to review it. If you have not done that, then you should review this CAT soon - and there are some basic questions that you should be able to answer (and the more EXACT you can be with your answers, the better):
After reviewing each section of this recent CAT, how many questions did you get wrong....
1) Because of a silly/little mistake?
2) Because there was some math/verbal that you just could not remember how to do?
3) Because the question was too hard?
4) Because you were low on time and had to guess?
5) How many Verbal questions did you 'narrow down to 2 choices' but still get wrong?
GMAT assassins aren't born, they're made,
Rich