GMAT Strategy

In the above assessment summary for verbal section, the SC has the highest accuracy rate (72%) but the lowest 'Average Difficulty Wrong Answers' (600). On the other hand, RC has the lowest accuracy rate (35%) but the highest 'Average Difficulty Wrong Answers' (660). However, my strongest area is SC only, and even though getting much SC ques correct, I am not getting highest difficulty level on those. And vice-versa for the RC section.
Let me re-assure - I can and I do solve higher difficulty level SC ques with ease.

Moreover, I have learnt all the strategies required and apply those as well. Also, I have been practicing for a long time (particularly on CR/RC). However, the results never reflect my efforts. My Verbal score stand in the range of 29 to 31. I really want to break this jinx.
Is there something in particular holding me back here at 29-31?

Thank you!!

It is tough to tell without looking at specific problems you are getting wrong. Generally though, people often struggle to improve their score because they are practicing bad habits. Are you making similar mistakes? Spend time to review each right and wrong answer so you become comfortable with the rules.

When I studied concepts, rules and strategies, I practiced without time limits; then, as I felt confident that concepts and strategies are imbibed in me, I went on timed sessions.
Accordingly I improved in the particular sessions for CR, but still no effect in the prep CATs. RC still remains the same; hardly see any improvement on RC. SC remains strong as usual.
People say that it takes time to imbibe all these concepts, but how much time?
Sometimes, I feel time pressure or concentration level affects. If so, how do I tackle this.
But, still if time pressure is the factor, it never hurts on the quant.

Moreover, the assessment summary confuses with the sectional difficulty level ques I am dealing with.