They call this "catching a falling knife", or more charitably "buying the dip". The conventional wisdom was that you shouldn't do this, because if it crashes to below $2 that's more likely to be because it's worth $0 than because of a glitch, and you're more likely to lose your money. But it's absolutely something you can try, and I wish someone with serious backing would try - I suspect the conventional wisdom isn't true any more.