What I usually do if prices are falling most specially if the coins are very low, I would buy more coins from a much lower price and your total amount of couns would then be divided; the result would be lesser losses. Read or research on google about books or ebooks on trading.
Indeed same as you I also did that strategies. If I have saw that coins is falling I will buy a lot of it and hold it until it pump again. Then I will sell it and wait to fall again and the cycle will be repeated. In that process you could gain a higher profit. And make sure that if you have seen that coin is falling you mustn't panic because it may lead into yout loss.
What strategy you are telling is good for Bitcoin and good Altcoins , you cannot follow same strategy on shit or low capacity coins, as they will always give loss. First you have to check the details about the coin value and then but more on dip as you know that price will surely bounce back and you can earn profit.