GMAT Verbal Section | Re: SC approach

I was studying SC using Manhattan approach ,where I read the question and then use the answer choices to find the difference and then see which is the best comparing the ans choices. I was looking for better approach as my accuracy with this approach was around 60-70 percent.
I bought egmat sentence correction course ,they have a different approach where the first sentence is bisected into clauses and analysed.
The question I have is,
1) While in their videos the egmat team bisects the questions