When I made my T-beam strongback, I gave it a coat of some left-over polyurethane/stain. I assumed that since warpage is due to moisture leaving or entering the wood, if I sealed it it wouldn't warp on me. Well, it didn't warp on me, but I'm not sure whether it was the sealer or just good wood.

A little twist isn't a problem as long as it doesn't twist any more once you've mounted the forms.

Dean