He invested BTC79.9924*$21.5 (median price that day) = $1719.84
And he cashed out BTC28.3309509*$75.41 = $2136.43
For a USD profit of 24%. In BTC terms it looks very bad of course, but the key when investing in anything is always to diversify. Even though he lost in BTC terms I wouldnt say it was a bad decision to put money in sdice.
I absolutely would. If I hadn't put the money in sdice, I would have left it in my bitcoin wallet.
Any investment that does worse than a paper wallet (the bitcoin equivalent of burying your money in the sand) is a bad decision in my book.