I think y'all are overestimating the risk. He isn't throwing it away. He's mentioned here that it's max 1 trade of 1 share every 5min. The initial portfolio is very diversified, so barring a concerted attack this experiment's returns likely won't be much different from a random actively managed mutual fund -- with the advantage of having no management fees and no trading fees either.
Everytime you buy and sell a stock even if the stock didn't move and no fee, you loose at least 0.01 usd per share because of the spread. Ie. Apple trades 123.45 to buy and 123.44 to sell.
And he can stop the experiment any time.