We did ask our clients not to trade on 18 Dec 12 due to anticipated movement in Sensex or Nifty which can force you to take a wrong opinion of the market. Have a look at the intraday chart of Sensex/Nifty and you will realise that why it makes sense to avoid such days.
Just have a look that till 11 AM Sensex/Nifty was consolidating and moment RBI announced no change in its policy; market reacted with a downward bias.
This type of movement will take more or less most of the time and thus it is better to stay on the side to avoid being caught in the uncertainty and indecisiveness of the market. Just remember that staying on the side-lines is also a strategy as every day is not a trading day. You can also check out the impact of news on budget day which is also a big day from trading point of view.
You can avoid making any intraday mistakes by using the Jackpot tip of the day which is a single call of the day and it captures the intraday volatility in specific hot stock of the day.