I've had status matched twice: from DL to AA around 1997, and from AA to BD a few years ago. Both times were legit, in terms of changing needs and travel patterns (plus DL's making their program worse with the change to SkyMiles a bit earlier.) I wouldn't do it as a game, because I might need that match later on and because enough treating them that way could ruin legitimate matches for everyone. I've seen one example* of a benefit being taken away because people gamed the system. We don't need any more.

If people want to find out what matches are possible and get tips on obtaining them, the main thread on that topic is here.

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*AA's eliminating the exchange rate of 2,500 miles per 500-mile segment upgrade for people who could demonstrate inability to use them. That was fair for those in that situation, in the sense that you needed up to six of them to upgrade a flight that could otherwise be upgraded for 15,000 miles. Now, it's 500 miles per.