I might be mistaken but I thought the large elongated axle was to increase rigidity with suspension forks and the two sets of holes were there so that you could run bolts or a QR.....
Larger diameter spoke flanges and centre than the XC50 hub and double hole axle, one for skewer t'other for bolts as an alternative, the idea indeed being to make the connection with suspension fork dropouts beefier.
The flanges on the end caps were bigger too but it was found that they were too big to fit some forks so there were 2 sizes in the end.
The ovalised axle was to prevent it turning in the dropouts too.