Someone (name forgotten) is whinging on about how a big chunk of the DOW has not made money if you bought it 1997 and sold now. Sure. But don't say that's an argument against buy-and-hold. Most of the buy-and-hold stuff is based on 30 years -- for exactly this reason. There are a variety of shorter time periods in which you can buy at a peak and sell in a trough and breakeven or lose.
Besides, they're picking individual baskets of stocks, too, not even the whole DOW.