In my previous post, I mentioned the need for standard dropout thicknesses before quick releases could be adopted by racers. This was necessary not only for "neutral" support, but as I just remembered, even within teams. Back then, each racer usually had their frames made by their favorite builder, so within a team, you had bikes from a number of builders, all painted to match, but in fact quite different in their construction. Imagine if one racer had 3 mm thick rear dropouts, the next 3.5 mm, and another 4 mm! For each wheel change, the mechanics would have to loosen the "Frankenstein" nuts, then adjust the QR, then tighten the nuts. Wingnuts would have been much faster!
The concern for bending and breaking axles really started only with 6- and more speeds in the rear, which required more overhang of the drive-side axle. In the 1940s and 1950s, racers usually used 5 speeds, and this probably was less of a concern.
It would have been easy to alleviate the problem, which appears to stem from the groove machined into the axle for the keyed washer that helps when adjusting the hub. French Maxi hubs (not Maxi-Car) had a keyed washer only on the non-drive side. So you adjusted the hubs only on that side, leaving the non-grooved driveside portion of the axle stronger and less likely to fail.
Maybe somebody can make reproduction Campy axles that are grooved only on the non-drive side? Of course, you'd make more repeat sales if you made both sides grooved...
To put the "axle breaking problem" into perspective, I raced on Campagnolo Record hubs for 10 years, with 126 mm rear spacing, and I don't recall any axle failure during 70,000 miles. On the other hand, my commuting bike broke Record rear axles every 6 months. It seems that the torque from starting at traffic lights did them in. It appears that some products are strong enough for racing, but not for commuting.
Jan Heine Editor Bicycle Quarterly 140 Lakeside Ave #C Seattle WA 98122 http://www.bikequarterly.com