Don't make the mistake of taking this calculation of min as imaginary. This is true and it generally happens with the science students. That is because writing an essay is an art and science students lack the experience of this art. Although it isn't difficult to learn this art. And you can even master it by practicing. The purpose of this chapter is more or less to teach you this art.
I have a batch mate. His daughter has done masters in Sociofogy from Lady Shri Ram College, New Delhi. After this, she tried to attempt the IAS exam. Unfortunately she lost all of her attempts except the last one. That girl accidentally met me at the World Book Fair in Pragati Maidan, New Delhi where I went to participate. When she greeted me, I was shocked because I had known her since the time she knew only to cry and could barely speak. Listening to her greetings, it seemed that even today by way of uttering those words she was actually crying. I immediately thought of the 6-months-old girl and I could sense her untold sadness which really troubled me. I called her aside and we sat and started talking in a corner. My wife, son, my batch mate and his wife went to have a look at the books. She told me it was her last attempt at IAS. In May, she has the preliminary examination and the mains exam in October. Before this she had taken the mains exam twice, the first time she couldn't clear it, the second time, she did clear it but couldn't clear the interview. Since it was her last chance, she became very sensitive.
We talked to each other for about 3 hrs. She told me about her marks of every subject of both the years. It was very clear that she could score well in all the subjects except in essay. She was unable to score more than 40-50 (at that time it was for 200 marks). I thought if she could get 60 somehow in essay, then, her selection was definite. So I asked her to change the game plan. I wanted her to prepare well for essay now and not much for the other subjects. So I told her how to prepare for essay and gave her my book as well.
I am glad to say that neither did she disappoint her parents nor me. She got 25th rank and now she is an IAS officer. Myfriend's family got not only an IAS daughter but also an IAS son-in-law. A small weakness of not being able to write a proper essay was one of the major problems in her major success.
So, you shouldn't ignore this part. I am not saying that you should prepare for it on the cost of other parts. If you want to crack IAS, you shouldn't ignore any part of the exam, and especially, the essay. If you ignore this, then you shouldn't expect success. Perhaps, you are not able to reach the 75% mark, but, at least you would be able to score more than what you could with a little more practice and seriousness.