I would think that this axle wouldn't have been used for xc just because people bend regular axles too and I am sure with the cost of this axle people wouldn't have wanted to replace it. This was more designed for the mx scene and tt people where every pound counts.
The old issue of ATV Source I ordered from last year with an article about this axle came today. As soon as I finish reading it, I will scan it if anyone would like to read it.