Regardless of the strategy, the numbers are real. You started with $100, and ended with $655. The profit for that indeed is 555%. Now, that is "only" 10% better than buy and hold, but show me any other investment that will return 5x profits in 2 months.

For that matter, 10% profit in 2 months is by itself very good, for that translates to 60% profit a year which in stock or forex markets is amazingly high. And that is in addition to whatever profit there is in BTC price rise.