Broken eyelets in Mavic Open Pro.

I was truing one of my wheels (32hole Dura Ace hub and Mavic Open Pro Ceramic rim) and it was impossible to get it true. Some of the nipples started to get a bit worn too so I figured I'd rebuild it with new nipples and spokeprep.
As I was disassembling it I noticed that one of the inner eyelets had broken. Broken in this case means that it had sheared clean off around the bottom or outer eyelet. As I continued I found one more broken eyelet. At both eyelets the rim had failed too. I.e cracked around where the outer eyelet sits.
I have ridden Open 4CD and Open Pro rims since around 1995 and I have never had one fail in this way before (I have had walls blow out from being worn too thin but that is something else).

I wonder if this eyelet failure is actually a manufacturing defect with the inner eyelets being made too thin.
Any thoughts ?

Seen it before. Not often though.

Mavic covered the ones I saw as warranty but if you've overtensioned it they might not.

Had one open pro fail in a similar way also.

How do they know if I have overtensioned it or not ? According to the park spoke tension gauge I use the spokes all the spokes were just below the limits of the chart for the gauge I use.