http://btcdou5ipdmzh2qvn76az5pt6j6gn5mhwtfgb2tsa3hscmbqkdetrgqd.onion?i=whydoubling
One can sell bitcoin when the price is up, then sell when is low, then again buy when is up, and then again sell when is low. The only catch is that you need to know when is down to buy, and when is up to sell. But that is simple because we have a smart algorithm that analize the bitcoin blockchain and sees when is down and up, as per this graphic We are investing our bitcoin and double it every 3 days.