Sixer,

I've run into that "thought it was structural, but it ain't" problem more than once when walking on boards in an attic. The worst is when you step on the edge of a piece of plywood and discover it's cantilevered past the edge of a joist, and the whole piece of plywood starts to tilt down. It's a testament to luck--not my reflexes--that I've never gone through the ceiling with one of those.

However, to my discredit, I am still the only person I have ever met (or at least, who will admit it) who has managed to fall completely through a drywall ceiling. A bruised pride is a slow-healing thing. [Linked Image]

-John