I think the whole thing started as a lark because Twitter is personal to him and he knows better than everyone. Maybe he sold more shares than he needed while

I think the whole thing started as a lark because Twitter is personal to him and he knows better than everyone. Maybe he sold more shares than he needed while he was at it; like you'd withdraw a bit more cash than you really need at the ATM. Then the market down turn sobered him up. Simple.