Lots of people have trouble with those timesaving strokes known as "Briefs and Phrases."    They are great when they work, but horrible when they don't.  As you go up in speed, you must make choices about them.  If you hesitate for one second at 225, you have let four words go by.  If you write out almost any Q&A phrase, you end up writing very simple words that are no trouble. 

Ultimately, the hesitation is worse than writing out the phrase.  Keep that straight.  Writing out the phrase is always a correct choice.  Hesitating on the phrase is always incorrect.  If you use the brief or phrase, it must be without hesitation.

Briefs and phrases are great to know, even better to know how to use.  But they will never be part of your base speed.  They are for emergencies.  They help you get out of trouble. 

Briefs and phrases are little bonuses to ease your burden.  But you can't depend on them.  They do not consistently appear. 

One section has a lot of briefs and phrases.  So you do well.  The next section has very few.  So you do not so good. 

It is nice that you performed so well on the first section, but you won't be passing many tests until you can do the second section.