PDX,
You might want to check out this thread:
http://www.ericsonyachts.org/infoexc...=sliding+hatch
The teak "veneer" is 1/4" as are the baltic birch plys for a total
thickness of 3/4 ". Yes it would support the weight of your average
human, but mine lives under a dodger and a sea hood, so it never sees
that kind of abuse. The bending form is strictly that, and is not part of
the finished piece. If you are building for strength, then bent laminations
are the way to go with the grain oriented in 90's or 45' to each other.
I don't like the idea of kerfing plywood to achieve a curve especially
when you need max strength for a given thickness. If you are looking
at alternative construction, a better solution would be coopering solid
wood into a curve, and adding splines for additional strength.
Martin