I just found the answer to why two identical applicants can have a totally different outcomes. The key is the IO professionalism. A very professional Asian American Officer interviewed me and she seemed to know her stuff. First she put me on ease, I guess I looked nervous, and asked me to realax and take a deep breath. Now the interview begins, she went through all my application and made sure I understood the questions and when we got to the Selective Service question she asked how old I was and I said more than 31, she said never mind about the Selective service letter. She also understood the 4 names system we use in my country and saved me from explaining it. She also complimented me on me achievements. She was a real human that felt what we went through to have the honor of U.S Citizenship. Then she asked if I want to change me name and then proceeded with the test. I answered 6 Qs correct and she moved on. Asked me to read a simple question and write the answer. She Approved my case and offered me to have the oath on the same day which I gladly accepted.
A few helpful points:
1. GC, DL and All Passports are a must have items. They even copy the 1st page of your passport before you set in for the interview.
2. Arrive like an hour early, security line takes too long, about 30 to 40 minutes to get into the building.
3. If your case is marriage based bring marriage certificate and your spouse's prove of citizenship.
4. Send ALL the supporting documents with the N400 so the IO can review them before hand and you have a short interview.
5. Don't park on the street and you will have a piece of mind, you already spent tons of money on this process, $ 12 more will not break the bank.
6. Smile to everyone even if they are rude to you.
7. Be a good citizen
Special thanks to Big Joe, Jacko, Vorpal and Bobsymth who made my application looks smart and for the endless support and time they didecated to this great forum.
Thank you ALL and good luck.
10/18/2011: N 400 Mailed
10/21/2011: N 400 Delivered
10/26/2011: Check cashed
10/28/2011: NOA recieved
10/31/2011: FPN received
11/04/2011: FP done W-I
11/28/2011: Inline for interview
12/19/2011: Yellow Letter
01/06/2012: Interview Scheduled
02/16/2012: ID, Approval and oath