> similarly well on most of the tests From your link they checked exactly one thing: shivering response to cold following breathing exercises. Both twins did e

> similarly well on most of the tests From your link they checked exactly one thing: shivering response to cold following breathing exercises. Both twins did exactly as well on this one test. That's not "most tests". It's one test. And personally, being able to withstand cold is the least interesting claimed benefit of breathing techniques.