Many aspirants go with the very strategy of preparing a subject from last ten years papers. You can go with this very strategy, too. But It's not good to not look beyond any aspect that has been asked or mentioned in the pas papers. As many new developments and dimensions come with the passage of time and are also included in the upcoming exams by the paper-setters. But here is a tip for the above-mentioned strategy. Whenever you read a topic from the past papers, look and read it from each and every angle and correlate it with the present scenario.
It's your score in the written and your ability for the job that are judged and seen at the time of interview. No much worry about anyone's previous poor or average academic background.

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"But screw your courage to the sticking place,
And we'll not fail." _Shakespeare, 'Macbeth')