The Motley Fool is back with a genre piece I've written about before: the crash shopping list. This time it's three growth stocks to buy hand over fist if the market crashes, built on the argument that the market is sailing into a growing set of headwinds. I don't doubt the headwinds. I've been writing about stretched valuations myself for a month now. But the phrase "hand over fist" deserves a slower read than it usually gets.

What bothers me about pieces like this is that the premise and the advice don't line up. If you believe a crash is coming, the disciplined move isn't to pick three growth stocks and wait to pounce. It's to keep your regular buying going through the decline, whatever the market serves up, because timing the bottom has humbled smarter people than either of us. In my experience, growth stocks often fall hard when the tide goes out. History's clearest lesson on that point is the dot-com crash, when the high-flyers of the late nineties came down and plenty of them never came back. One episode, granted, not a law. But a shopping list that assumes you'll calmly buy names that are down 50 or 60 percent is a list written by someone who hasn't watched their own account do that.

The Fool's underlying instinct is right: downturns are when future returns get made. I've said it here more times than I can count, and I'll keep saying it. My belief, after watching a few of these cycles, is that the person who kept buying a broad index fund through the worst of 2008 and 2009 generally fared better than the person who sat in cash waiting for clarity. The instinct is sound. The packaging turns a slow, unglamorous process into a snappy list of tickers, and that's where these pieces lose me.

If you enjoy following individual companies, and I do, a fair version of this exercise looks different. You write down the three names in advance, with a price or a valuation level at which you'd actually buy. You decide the position size before the fear arrives, because fear is a terrible portfolio manager. And you accept that even then, you're making a bet on a handful of businesses rather than owning the whole haystack. I hold a few individual stocks myself, sized so that being wrong about any one of them wouldn't change my retirement math.

For most readers, though, the crash plan doesn't need three tickers. It needs one: a broad index fund, an automatic contribution, and the good sense not to interrupt it. Serious drawdowns have shown up regularly throughout market history, and I expect another one eventually. When it comes, I'd wager the people who quietly kept buying will be the ones telling the story ten years later. The ones who bought growth stocks hand over fist at the bottom they guessed at will mostly have a more complicated story.

I'll give the Fool credit for one thing. Pieces like this get people thinking about downturns before they happen, and that's worth something. Thinking is fine. Just do the arithmetic on position sizes and cash reserves now, while the weather is calm, instead of improvising when it isn't.

As always, this is my perspective after forty years of managing my own money, not professional financial advice. The standard disclaimer, but I mean it.