BobN wrote:

You can try the "sagulator" - a calculator for determining wood
deflection. For your dimensions (36x22), red oak sagged .04". They
didn't have oak plywood. Maybe someone can tell us how oak plywood
compares to solid oak strength-wise.

Well, here's all you would ever want to know...

http://www.fpl.fs.fed.us/documnts/fplrn/fplrn059a.pdf

It shows that basically there's only about a 10-20% difference for same
species as compared to ply--somewhat less than I'd have thought. I
skimmed the (somewhat lengthy) report and if I got the gist right, it
concluded for there testing the difference was within the statistical
uncertainty. (Longitudinal to face sheet comparison)

I also found to my surprise that my impression that the laminating had a
significant effect on the transverse bending moment was also mostly in
error--there's an effect, but it's not nearly as large as I had
expected. I suppose my perceptions were flawed owing to the fact that a
4x8 sheet is only half the width in the transverse direction so the
impression apparent strength in that direction is amplified
artificially.