I was reading about the grading of steel bolts
(http://www.sizes.com/tools/bolts_SAEtork.htm.) At the end it made
this interesting statement:

"It isn't always a good idea to replace a bolt with a stronger one.
Some bolts are deliberately chosen so that they are weak enough to
fail before the stress or strain damages some more expensive or
critical part of the equipment. For the same reason, in making
furniture cabinetmakers use glues that are weaker than wood. That
way, if the furniture is overloaded, the joints break. It is much
easier to reglue a broken joint than to replace a piece of broken
wood."

Is this true? I recall reading on this NG that regular wood glue
forms a bond stronger than sold hardwood and when tested the wood
breaks near the joint before the joint separates.

Thanks,
Michael