[Rick H]

I have to admit to not fully understanding the proposed solution - but two things to be aware of are local bearing failure (i.e. tearing of thin steel around the bolt) and block shear failure if the bolt is close to an unstiffened edge (think pages in a ring binder). These two modes of failure should be greater than the shear capacity of the M12 bolt to allow it to reach full capacity. Welded-in bosses will help this - but only locally, they may just transfer the problem elsewhere, it's difficult to judge without seeing a sketch.