yes. I have two attempts (total five attempts 3CSS and 2PMS), one CE2013 and the other KPPMS2013. Previously History of USA was not my optional.
In CE2013, I got 53 (KPPMS result awaited) but the reason behind my poor performance was that I couldn't fully concentrate on the subject.
I prepared 22 questions in all and I was in a position to attempt almost all the questions on the paper. Some of my friends in KPPMS got enviable marks in this subject and that's why I opted for this. I'll suggest the Majumdar book plus some other questions related to the WOT and post-modern American history.
If you want to excel in this subject, you must task yourself with selective study based on the questions asked in the previous papers and fully prepare those very questions. I do have the catalog of those very questions, if you need that ask me then, it would be my pleasure to share. Good Luck!

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"Success is not final, failure is not fatal; it is the courage to continue that counts" (Winston Churchill)