Im not whining, Im just perplexed. The guitar plays fine, the neck is dead straight, stable, with no other issues-and the action suits me. Truss rod works, but any tensioning results in back bow. Ive had this late 70s Ibanez Studio since the late 90s and Ive always left the truss nut loose or maybe just finger tight so it doesnt rattle or back out. When I do a setup, its at about 90% of what Id call ideal (I like some relief). Maybe the truss rod is too tight in the channel? Its a slim 24-fret neck so I cant imagine that it wont bend. I tried leaving it sit with higher string tension and loose nut, heavier strings (use 10s normally) and helping it along by pressing on the middle of the neck - and yet its always straight. Any other ideas?