I can remember two actual complaints...some had paper thin spots that could be broken through easily with a sharp object.
(So that means a whole lot more than two were really out there)

The response from the ivory tower was, the product was developed using FEA, and the thin areas in the mains were, at that time, considered deliberate.

I was also given examples of several builders who deliberately opened up/machined away those thin areas which I was told was for a reduction in Windage losses.

This wasn't a debatable topic at that time, and these are not my ideas. The corporate Gods had spoken, LOL.
I'm just the messenger so don't shoot.

for the price charged, I'd prefer overbuilt rather than under.