Originally Posted by
JohnDThompson
I don't see that the shelf provides any support for the type of load that the chainrings exert on the bolts. It serves to facilitate alignment.
Exactly. The fact that the TA design, which dates to the 1940s I think, is still used today, is evidence that chainrings do OK with no shelves there. If TA chainring bolts break, it's because they're too small and made of crap steel. Nothing to do with the lack of shelves.