The situation for investing in JD is a bit more complicated as you will need to take CLAM/BTC exchange rate into consideration as well. As you can see on https://poloniex.com/exchange#btc_clam, the exchange rate is very unstable (one year high: 0.0144 vs one year low: 0.00072). There is no guarantee that the rate will be stable in the future nor the rate will go up in the long term.
many investors earned a nice share with investing in JD but i agree that there is no guarantee that clams rate will be stable or going up
However you are guaranteed to earn more clams long term. Using that logic there is no btc investment that's good because btc price is just as unstable so why bother investing in anything?
I doubt anyone makes more BTC than good traders who can make several BTC per day on the price swings. The whales make god knows how much aswell. You could argue you might aswell learn how to trade or invest in other traders vs dice sites.