I think that we should sometimes demand particular proof P; and if proof P is not available, then we should discount seemingly absurd or undesirable consequences even if our theories disagree.
Possibly, if the theory predicts that proof P would be available, then the lack of such proof is evidence against the theory. Otherwise, alternate proof should be acceptable.
Possibly, if the theory predicts that proof P would be available, then the lack of such proof is evidence against the theory. Otherwise, alternate proof should be acceptable.