I understand what you're doing, but I think it's a huge gamble. If you don't know why a coin is rising, you are unlikely to know when it will fall as well. Especially if you are spread across a large number of coins.
It's worth it as an experiment with a small amount, but I don't think it's a recipe for longer-term success. There's no real way of knowing whether you are buying in at the peak with the majority of your coins. This is especially a risk when the whole alt market often moves together.