We make heavy walled steel parts and we've found that sometimes the parts can crack from sitting around too long before their first heat treatment. Residual stresses due to macro segregation in the midwall.
Once you bend it. Don't bend it back. Even if it doesn't break immediately, you've severly reduced its strength. I'm assuming you bent it 90 and you plan on bending it 180 opposite.
We deal in a large part with Caterpillar specifications and they reference A255 on their drawings. We also use Ste-Cal extensively but not by choice.
To clarify, I believe the discrepancies that is seen in the DI, at least between Caterpillar and A255 are probably just the programs that are...