rithish, no I wouldn't use fib lines by themselves. Fibs are areas to expect support or resistance, but you need to be reading into other things as well. I mainly use the 50 - 61 zone, ambush zone, for my fib trades. For example, if I were bullish and price began to pullback, I would buy a pullback to the 50 area.
Or if I'm in a trade and there's not an obvious resistance line then I will use fibs to find a target price. For me the most useful is the 50 and sometimes the 38. I usually delete all line except the 50 and 61. This zone is the decision zone in my opinion. The place where price is going to make a stand in one direction or the other.