Saddle Rail Failure? I've been running a non-brand name full carbon saddle for less than a year.  It lasted through a couple of crashes and 'cross season.  But when my usual ride stopped for coffee, I found out both rails failed.  When in alignment, the saddle held enough to get me home.

The break was right at the point where the Thomson Masterpiece clamp mechanism starts, not far behind the nose of the saddle.  Is there anything to be aware of about where the rails broke?   The seatpost is offset - does this mean I should be running a seatpost without an offset?  

I expected the failure at some point, just want to be sure there isn't anything I'm missing before shopping for a replacement.
The first issue with carbon rail seat posts is the lack of a standard for rail diameters.  This often leads to the seat post clamp being improperly sized when compared to the saddle rail.  

Due to the stress riser of a seat post clamp on carbon, an ill fitting seat post clamp can contribute un-necessary stress to the carbon rails.

Carbon is much more likely to develop stress fractures due to over tension of a seat post clamp\stem clamp\etc than aluminum or steel.  Because of this, and the above situation, proper tension of the seat post clamp (along with an anti friction paste) is paramount.

Personally I don't think standard carbon rail seat posts are worth the hassle (of fitting them propertly, tensioning them properly, etc) of saving 20-40 grams.  Double so if you are doing any type of off road riding (like cross) where the external forces at play are magnified.