India, Nov. 25 -- As the rupee threatened to breach the '90 mark against the dollar, the Reserve Bank of India (RBI) aggressively intervened to stall the free fall. On Friday, the Indian currency witnessed the second-sharpest intra-day decline in three years. Thanks to the intervention by the central bank, it was closer to Rs 89. Most experts contend that the regulator is unlikely to allow it to go past Rs 90 since it is a psychological barrier, and may drive the rupee further down. Hence, it is likely to hover between 89.5 and 90 over the next few weeks. But there is a growing feeling that unless there is good news on the external front, the RBI's efforts may be in vain. Some paint an extreme pessimistic picture of an exchange rate of Rs...