"This above all, to thine own self be true"-William Shakespeare

I see what you're saying, but unless I want to posit that Jack and Sha're are gonna fall in love, I can't find a way to make that work. She might accept sharing Daniel but will Jack? Does Daniel want to share either of them? And, canonically, we're never gonna get a chance to know how Sha're might feel about it, so there's always gonna be that doubt in both men - would Sha're really have been accepting, would she have felt betrayed, would Daniel have gone back to Abydos and left me forever given the option, how would we live with ourselves if he didn't?