CAT aspirants must note that CAT is more about smartness than about intelligence. In CAT nobody expects you to answer all the questions. There should be an elimination round for the questions as well. You should know what to select and what to reject.
You have to be choosy while attempting your paper. There is no fun in getting 4 marks for a question and losing one mark for the next. So, unless you are very sure of the solution to the question, don't attempt it.
If you want to be the smartest, give priority to "accuracy". The act of choosing a question, in a way, is related to accuracy as you will select and reject a question based on the accuracy level you can achieve in solving the given question. 47 - 57 per cent of the paper done with 80 per cent accuracy will be much better than 80 per cent of the paper done with 47 - 57 per cent accuracy.
Do put in some efforts to improve your calculation speed. For attempting a question, we can divide time into two parts, to grasp the question and to calculate it further. Fast calculation will definitely save your time which you can then allocate
As we all know CAT likes to give us surprises. Over the years the pattern has shifted from pure calculation based questions to pure logic based ones.CAT 2012 also would not be exception, chances of tough questions will continue.