I have no way to verify the veracity of this comment, nor do I have any idea if it applies to the GP100 line.
That said, many years ago, I was talking with a fellow shooter and he mentioned that he had managed to destroy a Ruger Redhawk revolver with a badly constructed handload. Ruger offered to replace the gun at factory cost in spite of the fact that it was clearly (and admittedly) the shooter's fault. The customer service rep suggested that the shooter choose a blued Redhawk because he stated that the blued steel alloy that they used was somewhat stronger than the stainless steel alloy used in that gun.
Interestingly enough, around the same time, I came across some technical data for Beretta pistols, and they claimed that their stainless steel was about 30% stronger than the blued steel they used in their pistols. Just mentioned that to point out that there are a lot of variables. It's a mistake to assume that a statement like the one made by the Ruger customer service rep can be taken as a general truth applying to all items made from blued steel or stainless steel.