I don't think this is an investment strategy but one of the best strategy to make money in cryptocurrency space. Knowing the best time to buy, sell or hold is one of the qualities of an experienced trader.
Well no one would be able to time the market. Only thing what we should be aware of the swing is that how does the market look form the current scenario is on positive or sell side and accordingly if we can place the trades you would end up making money. Though one would not be always be able to make profits in trades at times be ready to book even loses as it is part of it.