Too much faith in the numbers provided by manufacturers of products.
Like: "this carbon fiber layup
is stronger than steel" (tell that to the crew of the Americas Cup boat that broke in half in light air in San Diego!)
"That Plexus bonding is stronger than weld" etc.
Even engineers seem to buy into this crap, but a lot of boats aren't really engineered.
Then there are the Bean Counters.... "is a keel
really going to fall off if we make the layup
thinner? No! If a sailor hits bottom hard that's not our fault!"