I can confirm that--it's exactly the reason S&W gave me when I discovered the frame of my unfired 442 was cracked underneath the barrel. I've seen identical cracks on two other NIB Airweights as well. Because the guns were all brand new and unfired, I've come to the conclusion that shooting Airweights with +P ammo is not what causes those frame cracks at all. Cracked frames are likely a pre-existing condition made worse by the stress of shooting ANY ammo.

In the link Osprey noted above, the poster shot 5 rounds of +P the previous owner had loaded in an unfired Model 38, and only then decided to "do a quick inspection". In all likelihood the gun was cracked before he ever started shooting. I strongly suspect most Airweight owners who discover cracks after shooting never inspected that area of the frame before shooting. (I know I never did until I read about the problem here on the forum.) So when they finally notice the crack, they wrongly assume that their ammunition caused the problem.

My own experience with cracked frames leads me to believe that the original concept of this experiment may be flawed--that shooting +P (especially in a K-frame revolver) is not what causes the "infamous cracked frame". It's good, though, that the frame window and b/c gap measurements were added soon after the test began, because that would be the most likely indicator of any problem--not an immediate, catastrophic failure like a blown cylinder or cracked frame, but simply accelerated wear or gradual stretching of the frame. Even then I suspect it could take more than 1000 rounds, and also think that those problems are more likely to occur on a lightweight J-frame instead of the beefier K-frame. So although some members are hoping for solid proof one way or the other, it's unlikely that a single mid-size gun tested for only 1000 rounds will provide any definitive answer to the question of whether or not +P can damage an Airweight.