Hi tina90,
After rereading these posts, there's nothing that specifically stands out as the 'cause' of what happened to your Verbal score on Test Day. As such, there are probably a variety of factors that contributed to that score drop. I'm going to list some possibilities, but it's up to you to really think hard about what occurred on Test Day (and even in the final days leading up to it).
I typically look for 'issues' that might occur during practice:
1) Unrealistic practice materials
2) Book-heavy study approaches
3) Skipping sections while taking CATs or doing anything else that would be considered unrealistic (pausing the CATs, listening to music, etc.)
4) Retaking CATs (and getting 'inflated' scores)
5) Seeing questions on your CATs that you practiced with or saw in these Forums (which would also lead to 'inflated' scores).
Since your CAT scores were all higher than your Official Score and you couldn't pinpoint anything unrealistic that you did, the focus then shifts over to Test Day itself (and the days leading up to it).
1) Lack of sleep
2) Change in 'routine'
3) Taking the GMAT at a different time of day (compared to the time of day that you took your CATs)
4) Skipping breakfast or trying foods/drinks that you normally would not have
5) Long 'lead time' between when you wake up and when you start your GMAT
6) Skipping the two 8-minute breaks (or not using them effectively)
7) Fatigue issues
Most Test Takers get to a point in the Verbal section in which they consciously think "I JUST WANT THE TEST TO BE OVER...."; THAT is one of the most dangerous situations to face, since the moment that "getting the Test over with" becomes the "goal", then accuracy, strong work, proper thinking, note-taking, etc. all gets throw out and even though you're reading the prompt, you're not processing anything, not doing work, etc. You just end up picking an answer that you think "sounds good." With a V19, that last part was clearly happening - you thought that you were choosing the correct answer - but you were not.
Going forward, I can't recommend that you continue to study in the way that you were studying Verbal before. A new set of tactics and resources is warranted (and you have to be ready to practice/commit to some new approaches).
GMAT assassins aren't born, they're made,
Rich