Publish without validation score?
You are right: decent journals/conferences are unlikely to accept a paper without a proper evaluation. Moreover the model is handcrafted, which probably means that it's hardly reproducible, right? And also that you can't do cross-validation I guess?

I think one would need pretty strong arguments to justify a contribution which has no scientific validation and cannot be reproduced. The only ways I can think of would be:


if the method solves a problem never solved before (or has specific characteristics which make it likely to solve such problem in the future)
if some sort of qualitative analysis demonstrates that the method is much better than state of the art approaches