I would feel better if market has not advanced so much when we encounter such extreme readings. in prior occasions you cited, each of them occurred in the bear market downtrend ...
in those occasions there was not much profits left for holders to protect - those who did not sell at the high pretty much resorted to just "sit" attitude.
Now there are tons of profit to protect even after such correction ...
not to mention soon afterward, lots of such profit would get the long term capital gain treatment.
As for no expansion of new low - imho, we wont see that until April or early May, as March 2003 low was an extreme. but there was good advances made in April and May. For example, by May, all NVLS needs is to down a couple points from here and it will be a new low. There are many stocks in such situation now.
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