blueman wrote:

My question was not so much about breaking the pins (which I imagine
would be hard to do) as about tearing out the hole.
What I really wanted to know is whether the**1/4"*pin*system*is
significantly stronger than the 5mm system to justify the bigger and
more obtrusive 1/4" holes.

I have torn out the 1/4" holes in plywood sides, but solid wood should be more
resistant. I don't know which you're using.

BTW, my shelves were only 30". I tore out the pins by bracing myself on the
shelf to get up from kneeling. I'm guessing that was only about 50 pounds of
pressure on the shelf, but it was localized to a handspan near the pin.

--
It's turtles, all the way down