If I remember right, those came out in 2002, maybe 2003. Yeah, I think it was 2003. The wierd design is so you could easily replace spokes. Trying to remember back to that Shimano tech presentation. I think 3 cross was the recommended pattern due to the spoke being pulled into the socket.
I can't speak of the durability issue. We never saw them on anything other than the demo wheel at the Shimano presentation.
Maybe others will have more info.
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