It depends on what market you are trading. If the liquidity /and therefore the demand and supply/ is enough you could always trade the way you do. But I think it's always better to know what the company is about and try to find some news about it.. In the developing markets /like the one in Bulgaria - Bulgarian Stock Exchange/ there are many underestimated companies that are just not in the public focus, so one could buy their shares without lifting too much the price. And when the company is discovered by the masses /or some news appears/.. the sky is the limit

It's always less risky to follow the trend but the great deals could come when you see something that not everybody sees.
I know that on the NYSE or some other well-developed market it's difficult for some good company to be let unseen.. But that's where our emerging markets come in place..
You could find some more info in my homepage if you'd like.