On Sunday, March 10, 2013 10:58:21 AM UTC-6, Mike Marlow wrote:
Didn't he just screw into 2 pieces of 3/4 plywood?

Yep.

If that's the case, then 1 1/4" is plenty sufficient. Especially after the head is countersunk. You only have 1 1/2" to work with if in fact it was 2 pieces of 3/4".

Yeah, I often overthink prevention and take precautionary measures, to prevent repeating past mishaps. Looks like he used course thread drywall screws. The tips are tapered, about 1/4" in length. Despite being countersunk, a full diameter of thread would not be biting into the wood at the tip end of the screw. Too often, I've had those shorter screws strip out. Using a longer screw makes for a bit more full diameter of bite and less chance to strip out, especially when I'm not careful during insertion.

What we may not be seeing, in those videos, is how many of those drywall screws stripped out or how many heads broke off.

Sonny